The first Iron Man movie set the bar so high. It's difficult to view another Marvel character movie without comparing it.
I think I'm going to place Thor just above The Incredible Hulk in terms of enjoyment. From top to bottom (so far) they rank: Iron Man, Iron Man 2, Thor, Incredible Hulk. (I don't count the X-Men movies or Spider-Man as they were made by Fox & Sony)
Thor stars Chris Helmsworth (Captain Kirk's father from Star Trek) as the arrogant god who is exiled to earth where he is supposed to learn some humility. On our planet he meets Jane (Natalie Portman) and supposedly falls in love.
The biggest drawback for me was the humor. There were funny moments that just felt forced. The first time Thor gets tased is chuckle-worthy; when he gets a shot in his butt in order to control him, I start to cringe. When they recreate the fact that Jane hit him with her car, I rolled my eyes.
What I absolutely loved about this movie was the "villain". I'm still not sure you could call Thor's brother, Loki, the villain. He is such a complex character in this film. There are plenty of twists and surprises from him as this movie progresses. I thought he was the best part.
Once the movie was over, including the anti-climactic scene after the credits, I felt like I had just watched a placeholder for The Avengers movie. I realize Captain America is advertised with that theme, but Thor just didn't pack the punch I was hoping for.
I'd give this movie a B-. Loki was superb. Like The Dark Knight, I was hoping to see more scenes with villain.