Rupert!!!!!
He was my favorite character of Survivors and is IMHO a perfect pick for Beorn, he has this ability to be nice and yet when he is mad . . . . not that Beorn got mad, but he wasn't all jovial and such. My only concern is, with virtually no acting experience what-so-ever, he might not be able to handle all of the things that go along with a film of this size, especially the vocal aspects.
Of course here I go on and on and the role hasn't even been cast yet
I truly cannot wait until we know.
Btw . . does anybody know if/when the movie is made (I'm not sure on the progress of that) who will be doing the casting? Because if it's the same people who did LOTR, we have a pretty good chance of getting the appropriate people, whoever they may be.