The interesting thing I've noticed in my multiplayer habits is that there is no room for being exceptional at a wide variety of these types of games. Out of the dozens of multiplayer games that came out for PS3 and PC this year I only had time to really get into the games listed below and especially this years winner: Battlefield: Bad Company 2.
It takes a lot to pry me away from my Left 4 Dead and Team Fortress 2 mouse and keyboard experiences. Thus far every Resistance and Killzone game I've played exclusively for a Playstation console feels somewhat off. Couple this with the questionable audiences of the recent Call of Duty games and you can see my apprehension prior to be playing a game like Bad Company 2.
When I was invited to participate in the beta of Bad Company 2, I had that feeling that seldom happens when you touch, taste or experience something you know will hook you. This game, rife with bugs and exploits [seriously, sniping with a shotgun?] continues to be my game of choice when I turn on my PS3. Not only this, but its helped me loosened my grip on my mouse and keyboard and made more open to multiplayer experiences found in Transformers: War For Cybertron and Red Dead Redemption.
All these things, and I get called fewer racial and homophobic slurs, than in any other console shooter I've played in 2010.
Honorable Mention: Red Dead Redemption, Transformers: War For Cybertron, Super Street Fighter IV