I really enjoyed it. And the third book is my favorite of the books too, so it is the one I'd be the hardest critic on. They cut a lot, but I was okay with it. With the books getting longer and longer, they're going to have to cut more and more to keep the movie to 2 and 1/2 hours or less for kids. They are faithful enough to the books to keep the story flowing the same and, I think, inspire those that haven't read the books to do so.
As for Troy, it is by no means faithful to the Iliad. Character's motives, actions, and their outcomes are drastically altered, as is the plot. If you're looking for a retelling of the Trojan War, run far, far away.