I actually prefer the Lord of the Rings films to the books. I find Tolkien to be too wordy and the books drag at times, becoming progressively more exciting as you go. Of the three, only the Return of the King was a can't stop page turner for me. I think Peter Jackson distilled the books down perfectly into a more concentrated form of awesome.
My fear (again, I'm kind of speaking out my ass here because I haven't seen any of the Hobbit films, but hey, discussion is fun) with the Hobbit is the opposite of what you're suggesting Steve. I'm not worried that PJ changed the story or didn't stay true to the book, I'm worried that he stayed too true, not to the Hobbit, but to the peripheral stuff. The Hobbit is like a pamphlet, you can read it in a day. There's not enough there for three movies. But Tolkien wrote and wrote and wrote all kinds of history, lore, fables, myth, short stories, sketches, poems and on and on. Stuff that never appeared in any proper book, but published as a view into the history and lore of middle earth. That stuff wasn't in the books because it wasn't good enough, or didn't belong. So why is PJ bringing it in the movies?
Again, speaking out my ass. I may end up finding them to be the best things ever.