Mass Effect = low frame rate and as i said previously features selective AA
Fallout = No AA/selective AA depending on platform
Forza = low frame rate and hardly a graphically complex game. Limited cars on track, poor background scenery, poly count, textures, platform exclusive, list goes on.
Gears of War 2 = selective AA, low frame rate, platform exclusive big budget
Gears of War 3 = No AA, low frame rate, platform exclusive big budget
God of War 3 = MLAA (which doesn't make sense since it's an ATi rendering method) but either way FXAA and MLAA are rather limited techniques, exclusive big budget title, and although capable of 60fps it averages significantly less
GT5 = incredibly big budget, platform exclusive, lets not ignore the frame rate issues that plauged it, and like Forza it's graphcis are rather simplistic, and it too has selective and limited AA
I mentioned AA as that's what someone above said was a defining feature of this generation.
As for Bioshock 2, according to beyond3d and everything i can find on the next. The Xbox 360 version does not feature AA, but rather filters. Also low frame rate to boot.