Patch 1 for Gears of War. It addresses the same issues as the original patch 1 (Live Update and performance), so I'm not sure what the "revised" moniker describes exactly.
The Gears of War for Windows Title Update fixes various performance issues, including the Games for Windows LIVE update issue.
This update is only compatible with the North American, South American, and Western European versions of Gears of War. If you are running the Russian or Eastern European versions of Gears of War then you will be unable to install the update. The Eastern European versions of the game include the Polish, Czechoslovakian, and Hungarian language versions of Gears of War for Windows. This has no impact on single- or multiplayer gameplay/connectivity.