Originally Posted by GAC
I'd assume that since part 2 is titled "There and Back Again", which was the title of Bilbo's book about his adventures, that part 2 will center more on the diminishing role (aging) of Bilbo, and the "passing of the torch" to Frodo.
Here is what I would do: split the movie in two about the time they enter Mirkwood or maybe after the giant spider attack. Part 1 would have the trolls, the goblins, gollum & the werebear. Part 2 would have Mirkwood, the spiders, the wood elves, the mountain, the dragon & the big battle.