Well, my top ten:
1. Slumdog Millionaire
2. Entre les Murs (The Class)
3. The Dark Knight
4. The Wrestler
5. Kung Fu Panda
6. Milk
7. RocknRolla
8. Burn After Reading
9. Rambo
10. Wall-E
Honorable mentions:
Frost/Nixon
Revolutionary Road
Tropic Thunder
Iron Man
Gran Torino
Hellboy II: The Golden Army
The Curious Case of Benjamin Button
I think 2008 was a fairly decent year for film, nothing like the early 2000s; by my count I saw 38 2008 films, which is a lot more than the number of 2007 films I've seen, admittedly a lot of junk in there, I've yet to see In Bruges, or Let the Right One In, which have many numerous appearances in those year end lists