Head over to CHUD.com, they have a full transcript of the THOR cast and crew interview panel and some of the discussions from Hiddleston and Branagh regarding Loki is very interesting, particularly since you say he's really the hero of the movie.

Aw man! Well let's just say the postbcredits bit made me squee because it sets up Loki for The Avengers (Hiddleston's casting in that already confirmed anyway).