I think it all depends on where you're looking for your filmic quality personally.
Yeah as far as the big US Summer releases go, the year could be seen as a disappointment, but when I can sit here happily and rattle off films I've loved the likes of Kick-Ass, Animal Kingdom, Une Prophet, Centurion, Inception, Daybreakers, Scott Pilgrim, The Social Network and Exit Through The Gift Shop, along with films I'm yet to see but I know will be good and am excited by like Shutter Island, Toy Story 3, Winters Bone, The Town, Jackass 3D, Agora, Detective Dee and the Mystery of the Phantom Flame and True Grit - I have to say I just can't get too down on 2010 as a filmic year.
...but then I've stopped looking to the major blockbusters for my movie fix as a rule. There's so much more interesting things going on in the US indies and docos or in foreign films that a hundred Prince of Persias, Clash Of The Titans or Alice In Wonderlands simply aren't the movie deal breaker they would have been for me ten or fifteen years ago.