The Avengers is out in the United States this weekend, and it's everything you'd want out of a superhero movie. Best of all, you finally get to see Nick Fury in action. Just don't see it in 3D if you can avoid it. As a post-production conversion, it adds absolutely nothing to the movie.
Do stay all the way through the credits, though. The scene in the middle of the credits is your typical Marvel teaser for the next movie, but the one all the way at the end (filmed after the premiere) is really something special.