In my profession, I tend to change computers a lot. Thankfully, I get Macs. We gave away our PC to a friend, and needed to save my wife’s bookmarks on my MacBook, until we get a replacement. On a Mac, it is very easy to transfer all of your personalized preferences from one computer to another. Going from a PC to a Mac takes a few more steps, and you can’t transfer everything as easily.

I usually only want to save my preferences when I get a new computer, just because I like fresh installs of all my software. I know it is a lot easier to use Apple’s Migration Assistant, but this is how I roll.

To get everything from one Mac to another, all you do is go to [username]/Library/Application Support/Firefox and copy the entire Firefox folder to your new computer. You can do this with any application you have on your computer. It copies all of your information, preferences, plugins, and history. Very slick.

From a PC to a Mac, I could not find a way to export everything from Firefox to my Mac. I can export the bookmarks, but that is it. My wife wasn’t too happy about that. All she really cared about were her bookmarks, though. When you tell Firefox to import from the file menu, it only asks to import all your preferences from Safari. You can do that if you have been using Safari, but it is better to go to the Bookmarks menu, choose “Organize Bookmarks…”

You will want to click the “Refresh Favorites” or settings button, and choose import HTML. Choose your bookmarks.html file, and it will import the PC Firefox bookmarks.

Or, just as easily, use the File->Import Bookmarks in Safari and import them into Safari, and then you can get all your Safari bookmarks and your PC Firefox bookmarks in one fell swoop.

Related research and analysis from GigaOM Pro:
Subscriber content. Sign up for a free trial.

• Virtual Worlds: Trends and Opportunities
• Why iPad 2 Will Lead Consumers Into the Post-PC Era
• The Near-Term Evolution of Social Commerce

When I first heard that Mail would be offering RSS support in Leopard my first thought was, “finally”. After installing Leopard I immediately opened up NetNewsWire and exported my subscriptions as an OPML file, only to find out that Mail wouldn’t accept it. Mail isn’t alone in missing this very important feature, Safari doesn’t offer OPML importing either.

If you have been using Safari as your application of choice for reading RSS feeds you will be fine, it’s a simple mouse click away to bring them into Mail. But Safari for the most part is nowhere near powerful or feature rich enough for most of us.

So what do I do now? Am I stuck with individually re-subscribing to all of my several hundred feeds all over again? At first this seems to be the case, but the long answer is: no. It involves a little jimmy-rigging and taking the long route but it is possible.

If you haven’t already, hop on over to Mozilla’s home page and download yourself a copy of Firefox. Once you have Firefox loaded visit their extensions page and install Sage, an RSS aggregator plugin for the Firefox browser.

After it is installed the Sage plugin logo will now be present in your menu bar. Export your subscriptions from your current feed aggregator as an OPML file. Once that is done simply click the Sage plugin toolbar icon and select the “OPML Import/Export” item in the options menu. Locate your subscriptions file and import them into Sage.

At this point you will notice that your feeds are now stored as bookmark files inside of a Sage directory in your bookmarks menu. Select “organize bookmarks” from the Firefox bookmarks menu and then select “export” from the File menu. This will place a bookmarks.html file on your desktop.

You are now ready to open up Safari. Select “Import Bookmarks” from Safari’s file menu and bring your recently exported Firefox bookmarks into Safari. A newly imported folder named “sage feeds” will now be added to your bookmarks. Weed out your other Firefox bookmarks leaving only the Sage directory and add it to your bookmarks menu.

This is the point in which it gets a bit scary. Make sure you select Safari as the default RSS feed reader in Safari’s preference panel, other wise this will not work. You will now browse to the sage feeds directory in your bookmarks menu and select “Open in Tabs”.

Depending upon how many RSS feeds you are subscribed to, Safari may take a few minutes to finish this task. It is important that you complete this step, if not Safari will only see your feeds as bookmarks, and not RSS feeds thus rendering them invisible inside of Mail.

After this is completed close Safari and open up Mail. At the bottom of the screen click the + and select “Add RSS Feeds”. In the pane that pops up, select “Browse RSS feeds in Safari Bookmarks”. At this point it is as simple as select the feeds you want to bring into Mail. After they are imported you can delete the feeds from your Safari bookmarks, and remove Sage as well.

Although it is possible to find a way to import all of your feeds, Apple made it nowhere as easy as it could be. Hopefully we will see this issue resolved in a future update of Leopard.

Related research and analysis from GigaOM Pro:
Subscriber content. Sign up for a free trial.

• A 2011 Green IT Forecast
• Green IT’s Q4 Winners: Wind Power, Solar Power, Smart Energy
• Report: Cleantech’s Third-Quarter Growing Pains