Stan Lee to Appear in 'Thor'

Well, no surprise here: Stan Lee will have a cameo in the upcoming 'Thor' film. On his Twitter page, Lee wrote:

Kenneth Branagh (of course I call him "Ken!") said my cameo's set for the upcoming Thor movie. --To him, it's a cameo, to me-- it's a ROLE!

The question is, which film will Lee NOT be in? Any guesses on his 'Thor' role?