If it did not have the love sequences between Portman and Hemsworth it would have been *cough* worth it.
Leave it to Hollywood to make dialogue awkward and cringe-worthy. It got good once the action started rolling, but there really was no chemistry between the two lovers, and Kat Dennings' character felt so forced I felt uncomfortable in the chair.
Special mention to Skarsgård for doing perhaps the best scene in the movie in which he uses shoes to explain the coming convergence. It looks like he had a lot of fun doing that and he seemed quite relaxed and confident in his role, unlike Portman who seemed off the whole time.