When Snow Leopard came out two years after Leopard, it provided a lot of UI refinements and some important under-the-hood upgrades for developers, like full 64-bit support, Blocks in Objective-C, Grand Central Dispatch, QuickTime X, OpenCL, native Exchange support and more. Mountain Lion is a similar upgrade — it looks to improve on Lion with a lot of UI refinements and some significant changes for developers. But instead of under-the-hood improvements, the most significant changes appear to be out in the cloud this time around.

Here’s the list of changes that Apple is rolling out, and how they will affect developers:

iCloud

iCloud can store both documents and key-value pairs. The important thing to keep in mind here is that the developer is responsible for collisions and conflict resolution between different devices updating the cloud. Documents have a dialog to let users select which version of a file they want to use. If you need to merge document changes, you’re on your own. Developers will need to think really carefully about how to manage conflicts when saving to iCloud if you are syncing data between multiple devices/computers. It’s not clear yet if apps signed by the Mac developer program certs can access data stored by apps signed by the iOS developer program certs. We will have to wait and see what Apple intends here.

While Snow Leopard added Exchange, and Lion added iOS-like features, I think Mountain Lion will be remembered as the “iCloudification” of the Mac.

Game Center

Something like 25 percent of titles in the Mac App Store are games, and the percentage is also quite high on iOS. I think there is a major opportunity here for developers to port games from iOS and keep high scores, achievements and friend lists in sync. iCloud support also means keeping saved games and game states in sync across devices. I’m not sure Game Center will ever be as popular with gamers as Steam and Xbox Live, but it could be great for casual gaming. I’d love to see someone come up with Xcode achievements so I could compare KLOCs with my friends.

Developer IDs, App Signing, Gatekeeper & Sandboxing

A lot has been written about sandboxing, which is coming to the Mac App Store and Lion, in advance of Mountain Lion’s release. I don’t think I’ll try to add anything to the discussion except to point out that Gatekeeper should help to educate users on what the differences are. It appears that you’ll be able to sign your apps — and gain the increased trust of users — without having to submit to the App Store and agree to sandboxing. Of course, to use the iCloud features and other goodies like notifications, you’ll probably want to go with the App Store anyway. Overall, I think this will end up being a good thing, despite the growing pains endured during the rollout.

Ken Case of The Omni Group is optimistic about the announcements:

This seems like a very big deal to me. Partly because Gatekeeper takes a more proactive stance against malware, preventing malware developers from producing new software which infects systems rather than always retroactively tracking down the bad software and preventing it from spreading further.

But even more important to me is that while designing this feature in a post-Mac App Store world, Apple went out of their way to build a mechanism which still supports developers who distribute software through channels other than the Mac App Store. It would have been much easier for them to simply say “to get malware protection, you must use the Mac App Store; otherwise any software you use is at your own risk” — but instead they’ve introduced a new mechanism for identifying trusted developers who distribute software outside the Mac App Store’s curated experience.

Color me relieved!

Sharing

Integrating single sign-on for Twitter in iOS led to a marked increase in people signing up for Twitter accounts. Just as Twitter integration didn’t kill the sales of dedicated Twitter clients on iOS, I would expect that the market on OS X won’t be affected much. Of course, Twitter isn’t the only way to share things. Flickr, Vimeo, etc. are there as well. What I’m really curious to see is if developers will be allowed to extend the sharing sheet by registering their own apps on the system. That could be awesome.

Apple is trying to make it easy to add sharing to an app, but the real issue here is figuring out if your app needs Twitter integration or not. I’m not sure I need to tweet my word count from within BBEdit, for example, but I do like the idea of tweeting what I’m reading right from within Safari, or what I’m looking at from within iTunes or the Mac App Store. I’m hopeful about this feature, as long as developers are judicious in putting it to good use.

Notifications

I think this is one area that developers should really work to adopt. I’m curious to find out more if Apple will allow online services to send notifications to apps as you can on iOS (where Facebook sends a notification to the Facebook app, and Strategery tells you when you’ve been defeated, etc.). Because of the infrastructure needed to handle those types of notices (especially at Internet scale), I would look into Push IO and similar services to leverage so you don’t have to build it all on your own.

What Else?

I’m sure there will be much more to come as Apple makes their plans more public closer to the summer launch, but I think there is a lot of good stuff here that developers can use to improve and build on their Mac apps. I think that iCloud integration will have the biggest long-term impact on OS X, but the refinements in app signing, sharing and notifications will be important features for developers as well.

What do you think will be the biggest change to the ways you make Mac software today?

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The Facebook features, which also include new Facebook fields for Contacts app entries, were originally spotted by iOS developer @jackoplane in the latest beta. Here’s hoping they actually ship in the software eventually, for the sake of both Apple’s users and Facebook itself . Both stand to gain from the social network’s integration in Apple’s mobile OS.

Users would definitely welcome a means to more easily share content, including photos and links, with their Facebook network, which has a much broader user base than Twitter. As for Facebook, there’s a chance to grow even larger thanks to direct, persistent access on the most popular mobile devices in the world.

Twitter integration has been a boon not only for the social network, where CEO Dick Costolo says it has helped propel growth to new heights, but also to services that depend on Twitter to enable content sharing. Music discovery service Discovr, for instance, saw sharing via Twitter increase substantially following iOS 5′s launch, while its Facebook shares remained relatively constant. Basically, taking away the need to login reduced friction and enabled more shares via Twitter’s service. Single sign-on for Facebook would likely have a similar effect.

I’d also love to see Apple offer a unified inbox, complete with access to Facebook messages, as an option in an upcoming iOS update. Since that’s not something we’ve seen yet with Twitter DMs (RIM actually wins on this one with its upcoming Playbook OS 2.0 update), I’m not expecting it anytime soon. But Facebook integration similar to what we’ve seen with Twitter could at least open the door to that possibility down the road.

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Simplified

The new app has a less complicated interface than the old one, in terms of having fewer buttons across the bottom bar, and fewer interactivity options for your main stream of tweets. It makes the experience and layout cleaner, but it also irks in some regards, especially for someone like me who manages multiple Twitter accounts. That’s because the ability to switch accounts is now located unintutively behind the “Me” tab, and takes two steps to get to from the home stream instead of just one, like the old “Accounts” button did. You can switch accounts by swiping left on the Me button, too, but it seems a little hit-or-miss.

The DM button is gone from the bottom bar, having been moved to the “Me” section, but once again, it introduces more steps, not less to get there. You can swipe up on the Me button to access your DMs from any screen, however. In the case of both changes, I can only assume Twitter found the average user wasn’t using either feature very often, and so they were better off out of the way.

The change to the tweets that appear in your home screen seem unnecessary even from that perspective, however. You can no longer access a quick menu of functions for each tweet on the home screen like you could before. Now you have to tap through to the post itself to reply, retweet or favorite the tweet.

Interactions

The new Connect tab features not only @mentions, but also a new “Interactions” section that details both your conversations and tells you about new followers, much like Google+ notifications inform you of new connections, in groups divided by days. It’s a small, but welcome, addition and should mean more users can turn off email notifications of new follows and still keep on that info.

Discover

One definitely positive change is the “Discover” section. It includes the ability to search Twitter, but also introduces more information and context for #hashtags and trending stories. You can see information about each popular “Story” listed, and then tap through for tweets that mention the subject, armed beforehand with some useful information about what the story actually means. It’s a big improvement for Twitter’s trending topics, and one that should serve the service’s efforts to appeal to marketers, and average users, well.

Better overall? Depends.

Overall, I’m seeing a lot of positive reaction to the aesthetic changes made to the iOS Twitter app on Twitter, and it definitely feels truer to Twitter’s brand than the previous, mostly generic incarnation. I’ll miss the in-stream ability to interact with content, however, which for me emphasized Twitter’s prioritization of communication above all else. Plus, it still doesn’t address the issue of the notification badge count remaining at one, and there’s still not a way to mark all your DMs as read at once. Despite its failings, I’m betting for the majority of casual users, with the addition of Interactions and Discover, this will probably be considered an improvement.

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Of course, the outage was annoying and inconvenient, and hopefully Apple learned a valuable lesson about managing a large-scale, persistent data service managed from its own server facility, and this will never happen again. But the extent of the outcry as the outage wore on, as well as the attempts on Friday to follow up and try to get to the bottom of what exactly happened, show that Siri’s effect on the mobile landscape is not insignificant.

It could be the case that Apple’s servers couldn’t handle the demand that Siri was putting on the system, as some users who contacted Apple support about the problem were told. That would indicate that Apple underestimated the scale of demand for Siri, which suggests the personal assistant is being used a lot. But even if the problem is independent of demand, the fact that the news of Siri’s going down spread as far and as quickly as it did, and elicited so much response from the user community, indicates that it is finding a place in people’s lives. Some of the media attention could be attributed to the fact that people love when a winner like Apple stumbles, but user concern seems genuine.

When Apple first announced the personal assistant software, I admit to thinking that Siri had limited value beyond triggering an initial feeling of novelty that would fade quickly. After using Siri myself, I found that it actually had a lot of real use value, even in countries where it hasn’t yet gained localization features. The indignation of users affected by the outage indicates that I wasn’t the only one who found myself leaning on Siri a lot more heavily than I expected to.

It’s not as widespread, but the outcry about Siri’s downtime reminds me of the web-wide groans that go up every time the Twitter fail whale makes one of its visits or when Tumblr takes a tumble. That’s a minor PR problem for Apple in the short term, but in the larger picture, it’s a very good thing that people miss Siri when she’s not around.

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Updating Twitter

To start using Twitter with Siri, you’ll need to set up your phone on your Twitter mobile settings page. In order to register your phone, follow the steps on that page by entering your country and phone number, then sending an SMS containing the word ‘GO’ to the number displayed. In the U.S., this is 40404. By doing this, you’re verifying your phone with Twitter.

Once you’ve done this, you’ll be able to tweet by sending an SMS to that same number. Add it as a contact in your iPhone’s address book, and then to get Siri to tweet for you, all you have to do is dictate a message to “Twitter.” It’ll then send an SMS with the tweet to Twitter, which will in turn post that tweet for you.

Posting a Facebook status update

To update Facebook, the same method applies. In order to verify your phone with Facebook, visit the Mobile Settings page and click Add a phone. You’ll be prompted to enter your password, and then to select your country and mobile carrier. Finally, text the letter ‘F’ to 32665. You’ll receive a confirmation code, which should be entered into relevant space on the web page.

When your phone is set up with Facebook, you can update your status in the same way as with Twitter, by sending a text to the contact with the Facebook number.

Make your (and Siri’s) life easier

If you find Siri cutting you off because it gets confused about Twitter, you could call Twitter “Twit” and Facebook “Face,” since those are very unlikely names to have in your address book (unless you have a very stupid friend, or you’re a member of the A Team).

If you have any other tips or hacks for Siri, let us know in the comments.

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[View the story "Twitter jokes about Siri" on Storify]

Seen any other great jokes about Siri, or have some of your own? Share them in the comments.

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Dorsey’s post, in which he points to a new discussion thread opened by Twitter in order to gather feedback about what tools and materials developers are looking for from the company, seems like a bit of a peace offering aimed at smoothing relations with a community that might be understandably skittish. In April last year, Twitter raised developer suspicion by acquiring Tweetie, a client for the service that had been independently operated by developer Atebits. Then earlier this year Twitter implemented new limits on third-party applications plugging into the system that prevented developers from accessing any of the real value of the Twitter ecosystem, as Mathew Ingram noted at the time. The company also bought another client, TweetDeck, in May, seeming to indicate that it wanted control over all major app and web-based access.

Twitter has been trying to turn the relationship around, introducing a dedicated site for platform developers in June, but it has a lot to make up for to win back developer trust. Persistent, system-level iOS integration could go a long way toward winning them back, but for that to happen Dorsey and Twitter need developers on their side as much or more than developers need Twitter.

For Twitter to capitalize on iOS 5 integration, it needs to make sure iOS app developers take advantage of that integration by building sharing options into their apps. System-level login will help put Twitter in front of many more users, but the service still depends on active sharing to exist, and third-party apps are the key to providing users with something they want to talk about.

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Facebook and Twitter share links are kind of a weird addition, if you ask me. Are people really all that likely to want to share basic information about available Apple products along with links for where to purchase them? I can see people maybe using it to brag about an upcoming purchase, but that’s about it. But it is something that’s been in place at the iTunes Store for a while now, and I suppose if even some people tweet or post about Apple products to their wall, the links will have done their job.

As mentioned, so far, these drop-down menus are only appearing for Mac Pro and iPod classic models. It’s possible that the role out was stopped midway, if it somehow contributed to the store outage, which web performance monitoring firm Catchpoint told GigaOM via email was network-related.

We’ll keep watching to see if these appear throughout the store, and let us know if you spot them anywhere else, too.

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For all the talk of social media services like Twitter and Facebook replacing RSS, I still find it to be the best way to get news quickly and efficiently, and it seems like Mac developers agree. A quick look at the Mac App Store shows quite a few RSS reader options, but here’s a look at three of the best: Reeder, NetNewsWire Lite, and Pulp.

Reeder ($9.99)

Reeder started its life as an iPhone app, got an iPad upgrade, and now finally has come to the Mac. This evolution helps explain why it looks and works like a Lion app already: It has fade-in scrollbars, multitouch gestures, and there’s even an option for monochrome sidebar icons, just like those found in the new Lion Finder.

Reeder only syncs with Google Reader, so you’ll have to set up a Google account if you want to use it. However, Reeder’s integration with Google’s web app is stellar. The keyboard shortcuts are exactly the same, and you can manage your Google subscriptions within Reeder by deleting feeds, adding new ones, or making folders. Sharing, starring, and noting articles can also be done in Reeder.

Reeder can share articles with numerous third-party services, including Twitter, Instapaper, ReadItLater, Readability, Pinboard, Delicious, and Zootool. Services can be individually disabled as desired, and you can add shortcuts for each in the toolbar.

Reeder offers a bevy of other customization options as well. You can change its appearance by choosing from two presets: one that looks like Reeder for iPhone, and another that uses standard OS X colors. These presets can be customized with a unique slider system, allowing fine-grain control over the UI. Keyboard shortcuts, multitouch gestures, and third-party services can also be customized to your heart’s content.

Reeder is a good app for power users and general users alike. It offers a lot of options, so power users can get their fix, but the interface is simple enough that new users should figure it out quickly. Since Reeder is also available for iOS, it’s a good choice for users with multiple Apple devices, since the Google Reader sync ensures your feeds and read items will be synced across platforms.

NetNewsWire Lite (Free)

Unlike newcomers Reeder and Pulp, NetNewsWire has been around since 2002, when OS X was still learning how to walk. Don’t assume that the app feels out-of-touch because it’s older, though. The latest release is a complete rewrite, and according to Brent Simmons, the developer, it’s the “best code I’ve ever done, by far.”

NetNewsWire has a more traditional interface than Reeder or Pulp, but it’s no more difficult to use, and it still looks great. It doesn’t sync with Google Reader, so all feeds are managed locally. The lack of Google sync could be a dealbreaker for some, but you can import and export your subscriptions in OPML, something Reeder can’t do.

Article Styles let you change the way articles look.

Another thing NNW has that Reeder lacks is Article Styles, which are six pre-defined CSS style-sheets that change how an article is displayed. You can customize these style-sheets, but it involves messing around in the app’s Resources folder, so it’s not exactly easy.

NNW has many limitations. It can only share articles with Twitter, Instapaper, and MarsEdit (a blogging app). It isn’t very customizable beyond moving buttons around and hiding the toolbar. It’s also 64-bit only, so it won’t run on older Macs with Core Duo processors. But if you just need a cheap, no-frills RSS reader, NetNewsWire Lite is your app. The little it does, it does well, and for free. It’s also worth pointing out that NNW is in a transition period, having been acquired by Black Pixel, and a more full-featured version should come out eventually.

Pulp ($9.99)

Pulp is relatively unknown compared to the other two apps mentioned, but it was recently featured in the Mac App Store. Rather than competing on features, Pulp’s big strength is its interface, which mimics a newspaper. It’s organized by pages and columns; each page can have multiple columns, and each column can have multiple RSS feeds.

Pulp is very easy to use, and offers a good alternative to using folders to sort content. However, the newspaper-like organization is less practical for users with lots of RSS feeds. I’ve had upwards of 4,000 unread articles in a single refresh, and the thought of trying to sort through that many with this interface is daunting.

Another unique UI element of Pulp is the Shelf, a wood-themed drawer that you can drag articles into for later reading. It isn’t going to replace Instapaper for power users, but for the average user, it works. Speaking of Instapaper, Pulp has it as an integrated service sharing option, as well as Facebook, Twitter, ReadItLater, and Readability. That’s not as many options as Reeder provides, but it should be enough to keep most users happy.

Like NetNewsWire, Pulp doesn’t sync with Google Reader, but it does have its own syncing implementation called Pulp Sync. Setup was painless, and worked as advertised on multiple Macs, even preserving my custom column configuration.

Pulp's article view wastes a lot of space.

The one thing I have to complain about in Pulp is how articles are displayed. There’s a huge chunk of wasted space devoted to displaying a reflection of the app’s main screen below the article. Clicking on the reflection brings you back to the main screen, but a simple back button would have sufficed. I’m not sure why the developer thought this was a good idea, and it’s disconcerting that it’s still there, since the app has already seen multiple updates.

Which RSS reader do you like the best? Is there one that isn’t on this list that’s better than these options? Tell us about it in the comments.

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Basically, WITH lets you tag another Twitter user (or users), and optionally take a photo of or with said user, then post it to both the WITH network and Twitter itself. You can also like the posts of other users, and use free and premium (available through in-app purchase) filters to add Instagram-style effects to the photos you include. The more you check in with specific people, the higher they rise in your profile. If you get close enough with friends through multiple check-ins, you can receive “special benefits,” according to Path. You can also follow and unfollow people on WITH, independent of whether or not you follow them on Twitter. There’s also a with.me web-based presence for the app, although at the moment it just points you to the App Store.

WITH is more useful than Path, because it doesn’t have any arbitrary limit to the size of your network. But WITH is also far more dependent on Twitter than Path, or Instagram, which is probably closer in concept. That’s a strength because it lets you sign on quickly and easily (you do have to provide your email in addition to your Twitter credentials, so it isn’t quite one step), but it also means that in many ways, WITH feels like a cool user-created feature for Twitter, rather than an independent, standalone product. Twitter’s @ replies and hashtags started out from similar, albeit more organic, roots.

WITH seems a little rough around the edges (figuring out how to post took a little while to figure out; it’s the person icon at the bottom in case you were wondering), but it seems like a more generally appealing product than Path. Plus, now that Apple has announced system-wide integration for Twitter in iOS 5, the fact that it relies on Twitter for its existence might not be such a bad thing, though Twitter itself is racking up a nasty reputation when it comes to playing nice with outside devs. We could see more apps like WITH betting heavy on Twitter now that it has the Cupertino seal of approval, however, so we’ll have to wait and see how the social network handles more attempts to exploit its services.

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