I went into this film with super high expectations and was not disappointed. As with the first film I found the relationship with Thor and Loki to be intriguing, complex and mystifying. You never know when loki is telling the truth or which side he really is on. Ultimately I think he is purely selfish and power-hungry and is on whatever side suits his interests. Yet the film keeps you guessing about his feelings for family. At some odd level, does Loki care for his brother? You be the judge.
The whole film is wildly entertaining and well thought out. The pacing rarely slows, which is a big difference from the first film. The quirky humor, present in Thor with the scientists (Jane, Erik, and the intern), has been brought into this film with a few twists that goes a little overboard in a few instances.
Another interesting part to this is a switching of roles with Thor and Odin. Whereas Odin was the patient all-knowing father figure in the 1st film; in this He comes off demanding, arrogant and a bit mean. It is Thor who seems to have it all figured out in this film, and his Father is the one schooled by him.
Despite a fake amputation of Thor's hand and brutal violence throughout, I feel this film could be handled by 13 yr olds plus, without any problems. Definitely worth your time.