Apple TV users can also grab iOS 4.4 for Apple TV (2nd gen models) now, which allows you to use AirPlay Mirroring.

In addition to users who will be downloading iTunes 10.5, released yesterday, in order to be able to install iOS 5 on their devices, the amount of software flowing from Apple’s servers as users upgrade this morning will likely put a heavy strain on its backend infrastructure. Hopefully Apple’s new massive N.C. data center helps it keep up with demand, but don’t be surprised if you have trouble connecting or encounter download delays.

Both iOS 5 and iCloud represent major changes and additions to your Mac and iOS device experience, so we have extensive coverage of both planned for the rest of the day. Stay tuned as we explain various features and also take you through the process of setting many of them up.

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Version 1.2 of the iPod nano software brings improved fitness features (which are better able to detect and track walking or running work outs), as well as the new single icon scrolling interface, which replaces the 4×4 icon grid. You can switch back to small icons or turn off home screen items altogether from the Settings menu.

Last but not least, you’ll get access to all the new iPod nano clock face options. There are 18 to choose from, so you shouldn’t get bored too quickly. I recommend the partial skeleton face with the exposed animated “movement” and second sub-dial.

The update adds a bit of individual personality for users and some very useful features, so it’s a nice free bonus arising from Tuesday’s festivities for existing iPod nano owners. Go ahead and grab it now by plugging your iPod into your computer and opening iTunes. If you don’t get prompted automatically, just hit the “Check for Updates” button in the iPod’s info screen.

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New owners of the latest Air and Mac mini will find fixes for issues related to flickering screens, booting problems when the power cord is attached, and slow running SD cards. Specifically, Apple says the update will:

• Address an issue that may cause the system to become unresponsive when playing a video in Safari
• Resolve an issue that may cause system audio to stop working when using HDMI or optical audio out
• Improve the reliability of Wi-Fi connections
• Resolve an issue that prevents transfer of your data, settings, and compatible applications to a new Mac running OS X Lion
• Resolve an issue where MacBook Air may boot up when MagSafe Adapter is attached
• Resolve an issue causing intermittent display flickering on MacBook Air
• Resolve an issue that causes the SD card slot in Mac mini to run at reduced speed with SD and SDHC media

If you have Lion, but not on one either the Mac mini or the Air, you’ll get a separate update that only pertains to the first four issues listed above.

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The OSX.MacDefender.A definition has been added to the OS X File Quarantine database, which means if a user downloads the malware, it will automatically pop up a dialog warning the user that the file will damage your computer, and provide an option to delete the file. The update also allows Apple to automatically update the known malware definitions list through daily updates. Users can opt out of this feature in Security Preferences, shown below.

The security update also automatically searches for and removes Mac Defender and its known variants upon install. If it detects the malware in your system, it will notify you once the update is installed.

It’s great to see Apple getting out ahead of this malware threat before it really gets out of hand, but as always, the first step to protecting your computer starts with you. Don’t ever install something when you’re not sure that it comes from trustworthy origins, and remember that if a website is telling you you’re infected without you having asked to begin with, it’s a safe bet that it’s not a genuine report.

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The update, which was reported to be arriving sometime within two weeks from April 7 by BGR, is also rumored to possibly bring fixes for roaming issues some Verizon iPad 2 owners are experiencing, but Apple makes no mention of the problem in its update notes for iOS 4.3.2.

The updates are compatible with the iPad, iPad 2, iPhone 3GS and 4 and the 3rd and 4th gen iPod touch. If you’re installing these updates today, please let us know in the comments how the new software is working out for you, and if you’re a Verizon iPad owner experiencing the roaming bug, whether or not 4.3.2 provides a fix.

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Here’s a complete list of what the update includes according to Apple:

This update contains improvements and other bug fixes including:

• Fixes an occasional graphics glitch on iPod touch (4th generation)
• Resolves bugs related to activating and connecting to some cellular networks
• Fixes image flicker when using Apple Digital AV Adapter with some TVs
• Resolves an issue authenticating with some enterprise web services

No update is yet available for the CDMA version of the iPhone released for use on the Verizon network. It still runs version 4.2.6, released in February. Some reports suggested that iOS 4.3.1 might bring battery life improvements, but if it does, Apple isn’t talking about it. Check out the update by plugging your iOS device into iTunes and hitting the “Update” button on your device’s  summary screen, and then let us know below if the fixes are working for you, and if you notice any other differences versus the previous version.

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It’s time to fire up Software Update! The latest version of OS X, version 10.6.5, has just landed. Aside from the standard “general operating system fixes,” there’s also a slew of specific ones addressing some common bugs, such as image processing in iPhoto and Aperture, and improved Microsoft Exchange server reliability.

The update weighs in at a whopping 517 MB, and of course, requires a restart once it’s done. I recommend saving what you’re doing and getting this installed as soon as you can. Cautious users may want to consult our guide to safely upgrading your Mac OS before running the upgrade.

Something I’ve noticed seems to be missing: The developers’ preview of 10.6.5 mentioned including support for AirPrint, one of the hot new features of iOS 4.2, but that isn’t mentioned in Software Update. Perhaps we’ll get more information about this when 4.2 is actually released.

So far, TAB staffers who’ve updated haven’t run into any problems.

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The updated operating system, previously known as the iPhone OS, features more than 100 new features. However, in order to download the 378MB update, you will need the latest version of iTunes (version 9.2), so be sure you are all up to speed before trying to upgrade.

iOS 4 can be installed for free on the older iPhone 3G and the current iPhone 3GS, in addition to the second- and third-generation iPod touch. An iPad-friendly version of the OS is expected later in the year.

The main features that the new OS offers includes multitasking, a unified inbox, folders for better application organization, the introduction of Game Center and more. Apple’s own site has an informative run-down of what iOS 4 brings to the table.

Check out the iOS update and let us know if you have any problems.

Regarding security, the update addresses several potential “maliciously crafted” attacks–are there such things as benevolently crafted attacks? One uses a color profile, which is inventive, if evil. Others use XML, shortcut menus, or the user’s desire to visit web pages or FTP sites of questionable virtue.

Sadly, as the Mac gains greater popularity, the mantra of “security through obscurity” becomes less and less reassuring. This is one area where Microsoft Windows and Internet Explorer may end up having an actual advantage over OS X and Safari, Windows having been forced to exist in a state of siege for so long.

As for improvements to stability and performance, it’s not just the usual boilerplate text included with the update this time. Besides supposed stability improvements for third-party plug-ins, the search field, and Yahoo! Mail, Safari 4.0.4  has “improved full history search performance for users with a large number of history items.” I’m one of those users, and I would cringe when going to “Show All History” and using the realtime search box. The first few letters would stall Safari every time, not so much now.

Safari 4.0.4 also improves JavaScript performance. Running the SunSpider JavaScript Benchmark, Safari 4.0.4 is 1.08 times as fast version 4.0.3 overall, with “significant” increases in many tests.

Finally and most importantly, Safari 4.0.4 does not break ClickToFlash. Upgrade (and restart) away.

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Microsoft issued updates for Office 2004 and 2008 covering security issues for both versions, as well as an XML conversion tool. The Office 2008 update also includes a number of minor fixes to enhance stability.

Regarding security, both updates address vulnerabilities “that an attacker can use to overwrite the contents of your computer’s memory with malicious code.” Opening a “specially crafted” Word or Excel file could grant the attacker the same user rights as the local user, including administrative rights if applicable. The XML Conversion Tool was also updated to address this issue.

The 12.2.3 update for Mac Office 2008 update also focuses on stability. In Word, general crashing issues have been addressed. The update also fixes the annoying text-spacing bug when opening some Windows Office documents. For Excel, crashing issues when using PivotTables has been addressed. PowerPoint also addresses stability. Apparently, Entourage is stable enough, though there is a new junk mail definition file. Finally, Microsoft Document Connection for the Mac gets several minor upgrades and fixes.

While this minor update is welcome, many Mac Office users are waiting for information about, if not an actual release of, Outlook for the Mac. In August, we learned Mac Outlook will be out by Christmas 2010, will be built from the ground up using Cocoa, and will have many features we desire, but since then nothing. How about an update on that?

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