I may take heat from my fellow Xbox brethren, but nothing really in comparison to the exclusives and awesome releases for the PS3 in 2011. 2011 will be the year of the PS3 in my opinion. 2011 is going to be a dud compared to 2010 for the Xbox 360.
The great games of 2010 (personal opinion here) are:
1. Red Dead Redemption
2. Fallout: New Vegas
3. Darksiders
4. Mass Effect 2
5. Assassin's Creed: Brotherhood
6. Fable 3
7. Halo: Reach (for others not me)
8. Call of Duty: Black Ops (for others not me)
9. Alan Wake (have heard great things but picked up Red Dead Redemption the same day this was released)
I was thorougly disappointed with Bioshock 2, hence I did not list it, because it was basically Bioshock with no Andrew Ryan, very little graphical updates, the exact same atmosphere and you play as Big Daddy instead of...I forgot the name of the protagonist in Bioshock.
If you are just coming back from a period off from gaming, then the games to buy are from 2010 or earlier.