I have yet to see LOTR though I will rectify that as soon as I recover from the impending holiday crush.
From what I understand though, Jackson tried to be as true to the books as possible. He did cut out a number of things that weren't central to the storyline. Had he not done so, I would venture to say that he could've made three multi-hour movies just from the first book.
One of the things I'm curious about, considering this movie isn't being preceded by The Hobbit is how they handle the matter of Gollum.