I've been re-reading the book and I've been thinking about where the movie breaks will be. Before reading it, I pretty much came to the assumption that the the original split was going to be after the Bilbo and the dwarves escaped the wood elves. As I'm reading through the Mirkwood chapters, I'm thinking that the first movie of the trilogy will end just prior to them entering Mirkwood (although I'm not sure how that gels with Gandalf's side adventures).
On another note, the whole time I've been reading, I've been trying to imagine Martin Freeman as Bilbo, and much to my surprise, I'm struggling. Not because I don't think he'll be good as Bilbo (on the contrary, I think he's going to be wonderful), but because Orson Bean's animated version keeps popping up in my head. This is probably because the 1977 animated film was a large part of my childhood, and after all of these years, despite it's corniness (at times), I still love it.
But here's hoping Martin Freeman replaces that voice next month.