OK I have a top ten now for 2012, based on UK release dates:

1. The Imposter
2. The Avengers
3. Moonrise Kingdom
4. The Master
5. Martha Marcy May Marlene
6. The Artist (cheating a bit there as it came out in one cinema at the end of December 2011 but oh well)
7. Beasts of the Southern Wild
8. Young Adult
9. Argo
10. The Muppets

Honourable mentions: Amour, Looper, Once Upon a Time in Anatolia, The Dark Knight Rises.