In my opignion, MGS4 takes GOTY hands down, that game is amazing, no question and wasn't rushed like Gears2 was. LBP is pretty good too, the most fun game this year for sure, still hope that the online gets less laggy because when its not its a lot of fun.
My favorite games for this gen:
1. Gears of War 2. MGS4 3. Killzone 2 4. Halo 3(Underated by many) 5. Mass Effect