I've been waiting to see the movie since it was confirmed 1-2 years ago. I'm not sold on dividing it up into several parts as the book really wasn't that long when compared to TLOTR books, which Peter Jackson managed to fit into 3-4 hour long movies, but then again they did have to cut out a lot of their story so maybe it will be a good thing.
Yeah, I was quite surprised when I heard that the book would be split into three parts movie-wise, but when I read the explanation/what Peter Jackson suggested, my fears were allayed. It's going to be exciting being able to see the additional material from the appendices and so on in a visual form.
I think the The Hobbit movies will basically add content on the return of Sauron as the Necromancer of Dol Guldur, the Dwarven rings and the One Ring, and the White Council meetings (Saruman, Elrond, Galadriel, and Gandalf). I'm sure that there might be more than what I just stated though.