On the other hand so much of the original story had to be cut out to fit everything in 2.5 hours (which is already pretty lengthy movie). I wonder if a mini-series would have been a better format for the movie. Plus it's kinda sad that the ending was slightly different. While the giant psychic squid would be a little weird, it's really no weirder than people running around in costumes fighting crime.
In the end I enjoyed the movie for its cinematography (it's gorgeous), and characters (excellently portrayed by the actors). If you liked the book, watch the movie. If you haven't read the book, read it first, then watch the movie.