Well GTA Iv, Halo 3 and Madden 08 are all set to release at the same time, and Microsoft is cofident these three games will make it a winner for this generation.
GTA Iv I hope is good. I didn't like GTA
A for the dated graphics and boring map, but if it is liberty city, and from what I've seen of tailors (rendered in the 360 gameplay) the game should be really good. The Airplanes, helicopters etc. got far to excessive in later games in my opinion. I just like to have cars, preferably really fast cars.