Theres been a bit of discussion about this in other places but it has recently been made almost official by CNN that Tom Hanks will be playing Robert Langdon.

Hmmm...Tom Hanks....Not bad but he wouldn't have been my first pick.

I would have probably chosen either Peter Krause or Aaron Eckhart (look 'em up on IMDB.com if you don't know what they look like.)

You can check out the whole article here.