For having to squeeze 600 pages into a 2 hour movie, Chris Weitz did a great job doing so. He kept the movie true to the book as he promised. There were some points that I wish were touched upon (the Rabbit, Charlie finding out about the Motorcycle, Volturi waiting room, etc.). But then again, when you only have so much time to work with, you do have to cut some things out. I liked the tweaks he had put in the movie as well. The acting improved a tremendous amount as compared to Twilight. The filming was much smoother. And, of course, the CGI was very impressive.
Overall, from a fans point of view, I was very happy with this movie, as it stayed very true to the book.