Battlefield 3, Skyrim, Assassins Creed: Brotherhood.
I just finished Assassins Creed 2, one of my favorite games in a long, long time. It really suprised me, the only issue I had with it was a lack of any real challenge to the missions. Brotherhood however, and I'm only a couple hours in, so far seems to have solved that by grading your skill in completing each mission. But going back to AC2, it really has it all - deep and rewarding gameplay, tons of customization, outstanding visuals and top quality music and voice acting. The game lasted me 33 hours which is a significant chunk of time, yet the pacing was excellent and the game kept introducing new wrinkles all the way through to the final credits. I'm officially a fan.