My nominees.
Heavy Rain - I know this game is very divisive, but it made me play a video game in a way I never have. Never have I TRULY thought about how my actions affected the characters, being that usually it didnt matter much in the grand scheme. I know ME2 is the same way, but I havent played it yet as I just got my 360 back.
God Of War 3 - Epic finale in the trilogy. Not only did the story finish on a high note, but they actually improved the combat which I was worried about. Add the even more improved presentation and graphics, and you got the whole package.
Red Dead Redemption - After GTA4, I was verry worried I was falling for the hype machine again. Im glad I didnt talk myself out of buying this game. Excellent game, I love how Rockstar made John feel so....human. I actually liked the family missions and Bonnie missions the best, because he seemed like a normal guy during those as opposed to a invincible gunslinger.
Honorable mentions - FFXIII and Splinter Cell:Conviction. Very close, but not quite at those 3 games level IMO.
I am a gamer. Not a fanboy, not a troll, a gamer. So when you dont like what I have to say, remember this fact.
