Lots of "Best Of" lists everywhere the next couple weeks, which is fine--and often fun. But I've always thought that the more interesting list would be "Most Influential." As in, what were the most influential movies of the decade, as opposed to the "best." I suspect that there wouldn't be much overlap between the two.
As a for instance, some version of the Lord of the Rings trilogy shows up on almost everyone's "Best Of" list. It certainly would be on mine. But I don't know that those movies were particularly influential, either on movies themselves or the industry at large. By contrast, the first X-Men now looks fairly influential because it proved that even a troubled, mid-budget superhero movie could make money. Which lead to the explosion of comic-book movies; the giant grossing Spider-Man series and Dark Knight; and the eventual independence (and then acquisition) of Marvel. Not a great movie, but a very important one for the business.
Artistically, I'm not sure what the most influential movies of the decade would be. Maybe someone else (Santino?) has thoughts on the subject.
Update: Galley Friend DR has an interesting version of this: A list of the most detrimentally influential movies of the decade. He includes 300, The Ring, and Saw.
45 minutes ago