Shooters are for children, they belong on PC unless they support M/KB like UT3 does. Warhawk being one of the worst games I've touched in years and gave it to a friend after an hour or two. I'm way behind though, too many games and too little time. Have yet to try MGS, GTA, Infamous, or other games that would likely go on this list. But from what I've played so far I'd vote in no order:
Burnout Paradise
Uncharted
LBP
R&C ToD
Rock Band 2
Dead Space
I know that's 6 but it covers the main categories.