Really fricking awesome movie. Top notch Joss dialog and funniness too, but the action was not only competent it was amazing from top-to-bottom.
The only reason I'm still slightly-less than hot for it (not lukewarm by far, but not red hot) is that I really don't care about any of the characters except Iron Man and Hulk, and this movie had the worst actor playing Bruce Banner I've ever seen. Really didn't like that guy.
Otherwise, delivered on all counts. Hoping Joss does the sequel, which was confirmed I believe.