This news comes via a Twitter conversation between Marvel Comics Editor in Chief Joe Quesada and Avengers comics writer Brian Michael Bendis...
Joe Quesada: Okay, three words describe my day today “Branagh gets it!”
Bendis: Hey are we allowed to talk about what we did today or is it hush hush?
Quesada: We can’t go into detail but I think we can say that we met with Branagh about Thor ;-)
Bendis: So we can’t go into detail but maybe we can say that we met with Branagh about Thor ;-)
Quesada: (in response to a fan) I’ll tell you what’s sweet -- Sweet is when he starts quoting continuity and past storylines. The man has immersed himself in Marvel.
Quesada: Yes we can hint at an hour super secret Thor meeting with Branagh, but don’t give it away, just hint.
It's always good news for the movie when a director takes this kind of interest with the comics!