Microsoft has confirmed that Games for Windows Live is not just for Vista but it also works on Windows XP. A lot of speculation was caused when Cliffy B announced that Gears would be available for both Windows XP and Windows Vista, and some rumors were started such as the one which said that there would be multiplayer only in the Vista version forming a sly tactic to force people to upgrade.

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When Cliffy B demoed Gears of War for Windows at E3 2007 to a throng of enthralled attendees, he let drop at the end of his presentation that Gears would be available for both Windows XP and Windows Vista this year. That caused no end of speculation, ranging from using GameSpy for online play in the Windows XP version to only allowing multiplayer in the Windows Vista version to force gamers to upgrade.

You should all breathe a sigh of relief and know that Games for Windows -- LIVE will work on Windows XP. When the development team was working on Games for Windows -- LIVE, they focused on a single platform to ship the first iteration of online play, and that platform was Windows Vista. Now that Halo 2 and Shadowrun are out and available, the team has been able to go back and finalize the work done to make sure Games for Windows -- LIVE works on Windows XP. Which means that not only Gears of War will connect to LIVE on Windows XP, but so will the other games we announced that will support Games for Windows -- LIVE, like Universe at War from SEGA (which, incidentally, will also enable cross-platform play between Xbox 360 and Windows PCs).