Here is all that was said about Thor.
"That turned out to be a positive for Chuck but a negative for director Kenneth Branagh’s movie Thor, which starts filming in January. Levi was cast as Fandral, one of Thor’s Warriors Three in the comic book adaptation, and the actor had even been working out especially for the role, but had to walk away when they got the extra pickup. (Levi admits that producers had asked him to audition for the role of the usually beefy God of Thunder, but told them no. “I’m tall and in pretty good shape, but I’m not big and girthy like that,” he says.) Maybe all that working out will help when he shares screen time with former wrestler “Stone Cold” Steve Austin, one of many guest stars on Chuck’s third season."
You could read the rest of the interview over at USAToday, though the part I posted is the only thing involving Thor.