Epic's Mark Rein lets us know what to expect from the next Gears of War patch in this post on the official Gears forums:
The next title update for Gears of War is currently going through the certification process. We'll have more detail about the update next week but I can tell you that in addition to fixing a whole bunch of glitches, and providing 720p for VGA users running at 1280×1024, it will contain a brand new multiplayer gametype called Annex.
There's no details on the new gametype except that "[testers say] it is our best multiplayer gametype yet."
I'm always glad to see new functionality added to a game post-release — it's a great way for publishers to keep a game in the public eye and (as long as it's free) gamers always appreciate new things to do in their old games.
via Kotaku