The Epic Games Forums have word from Epic's Mark Rein to expect a beta demo for Unreal Tournament 3 this month, maybe as early as this week (thanks Gamer's Hell). Word is:

Just wanted to give you a heads' up that we're getting pretty close to releasing the Unreal Tournament 3 Beta Demo for Windows. The Beta Demo will allow instant action play against bots as well as online multiplayer. The purpose of the Beta Demo is to test the game on a large variety of hardware configurations and get gameplay feedback from the community. The development team feels they're pretty close to being ready to release this so it could come out this week but for safety sake I'd say it should be out within two weeks.

We have a few fan sites in tomorrow to play the full game and I'm sure they'll be sharing their comments pretty soon afterward.