The medievalism in the film Thor has taken a long road from the medieval period to end up on the screen. By this I mean that, like most fantasy, this film will employ a version of the 'medieval.' Unlike most fantasy, however, it will not be a medieval-esque world that is invoked. Instead, it is reference to a very specific piece of 'medieval' mythology. The Norse legends were the inspiration for the comic book that would be the inspiration for the film. And so its reference to the medieval is more specific than most fantasy. And yet the world that is portrayed (or what I can tell from the trailer) is less trying to create an impression of something medieval than most fantasy. Instead Asgard looks futuristic, as does the wardrobe choices, with just a touch of the fantasy medieval being visible. Compare it to something, say, like Eragon or something aimed for children, where the feeling and atmosphere make use of a medievalism though nothing specifically medieval is referenced. For instance, there are dragons, but no mention of say Beowulf and his fight with the dragon.
I am interested to see how this will play out. I stand by what I said earlier, that I think that the film has no obligations to be true to the original myth, only to the comic book, and yet it will be interesting to see how mythological 'medieval' they decide to go.