Uncharted 2 - Best graphics ever in a video game, slick gameplay, great story.
Mass Effect 2 - Second best graphics ever in a video game, best combination of RPG and shooter yet, incredible story, only game I've ever played to truly continue playthrough from the first game using your saves.
Red Ded Redemption - Great graphics, GTAIV controls plus better targeting and health gameplay, great story and setting.
So far this year those are the top 3 I'd say. All three also have some of the best voice acting in gaming history. It's still early being July and all, but I don't see another game coming out this year other than maybe Mafia II that is going to trump these three.
Mass effect, red dead is good but not engrossing IMO.