Red Dead: Redemption, i probably think it's better now then i will in 2 years but imo it's the third best game that i've ever played behind only Zeld: OoT and Bioshock. Oh and of course Halo and COD: MW.
And how has no one said Dragon Age yet, that was a great one and i spent almost as much time on that as i did on oblivion.
Same goes for fable, both 1 and 2.
Fifa 10 based on the fact that it's the best soccer game ever made along with the most recent madden and nhl games.
Edit: How the hell did i forget Prince of Persia: Sands of Time, has to be in the top 10 ever, i loved that game almost as much as Yhatzee.