As far as films from books go, TLOR films have exceeded the generally expectations that previous experience has given me. Lets us be thankful it hasn't been the huge let-down of, say, A Prayer For Owen Meany/Simon Birch.
I really liked Gollum too. I liked the fact that he is actually made to be a little more three-dimensional in character (even if he is about 90% computer generated). Oddly, New Yorker film critic Anthony Lane criticized the characterization of Gollum, saying that an epic story doesn't need to explore motivations and emotions of characters.
One change that did disappoint me was the Ents. It has been quite a while since I read the books, but I pictured them as much bigger, especially in girth (more like Sequoia trees). Secondly, in the film they destroy Sauramon's factory/castle while in the book (if I recall correctly) they intervene in another battle and turn the tide. (Correct me here if I am wrong.) I think the director made a pretty heavy-handed choice to have the trees destroy the industrial baddies. I guess this is what passes for subtlty nowadays. In reading the books I had enjoyed the odd violence of the tree-like Ents crushing the hoards of orcs.
