The movie was stand-out excellent. By far the best movie in the Marvel collection. The plot didn't once make me roll my eyes (though perhaps the "archery" did), the fight choreography felt like comic book fights in the good way, Loki was loathe-able, Nick Fury kicked ass, and the movie belonged to Natasha Romanoff (Black Widow) and Tony Stark (you know who). Whedon does well with women & action as usual. Also, his dialog was completely in place. The movie was funny and the audience loved it.
Thumbs up! Might help to watch Thor first, though. I was pleased that Stellan Skarsgård reprised his role.
I hereby predict re-releases of Buffy, Firefly, Serenity, etc, with "from the director of The Avengers" plastered all over them.