Well this is a summary of my thoughts on the movie.
There were some really fantastic action moments, with the final battle having some unique parts. I also enjoyed the acting from Hemsworth and Hiddleston, who have good chemistry and embrace their roles.
But that's where my praise ends. First, I don't find Kat Dennings funny in the film, and that seems to be the one reason she is there. And then there's Natalie Portman, who I don't think is necessarily bad in the movie, but nothing special, and her romance with Thor to me doesn't feel believable.
I find the worst part of the film, though, to be the villain. The villain wasn't memorable, not having an ounce of personality. To make matters worse, his overall evil plot never gave the climax a feeling of urgency.
I don't think the Thor sequel is bad, it's entertaining, but I don't find it all too special.
Funny thing that happened in the theater watching the movie though. This lady sitting like three rows in front of me would like clap and laugh/giggle uncontrollably whenever Thor would do something or a joke would happen. At first I thought she was just an over hyper fangirl, but as it kept going I feel like she may have been high on something.