^ As I understand it, this movie is set in Asgard in ancient times, not modern times. I suspect that there will be some tie in with Don Stark and the hammer and the present day Marvel universe. However, I don't think they're going down the Ultimates route. I'm guessing that part of the reason that Branagh has been cast is his ability with older dialects - with so many Shakespearean adaptations under his belt, the 'Thee, Thou' dialogue of this movie will be a piece of cake.
Last rumour I heard was of True Blood's Alexander Skarsgard as Thor with his more famous dad Stellan as Odin, while Josh Hartnett was in the running for Loki. Before you all roll your eyes and groan, apparently his Kenniness was well impressed with Hartnett's Hugo, the Iago character in Tim Blake Nelson (another Marvel connection, incidentally)'s 'O', a high school take on Othello. Branagh himself played an acclaimed Iago opposite Lawrence Fishburne, so I guess he knows what he's talking about. Supposedly the Loki of this movie has shades of Iago.
I have seen one of the 3 Wallander adaptations shown thus far and have recorded but not watched the other 2 - I don't remember this co-star but will keep an eye out for him. Incidentally, isn't it funny how Scandanavians keep popping up in Branagh's career? Hamlet, Wallander, now the God of Thunder himself!