Just got back from seeing it at an absolutely packed 12pm screening, loved it, and i actually quite liked the new ending. The squid wouldn't have worked all that well on film, particularly as there are no hints about any such creature throughout the film (whereas we see a painting and other things in the book).
I saw it with two people who have never read the book, one of them loved it and now wants to read the graphic novel and the other thought it was "meh" (his worRAB), but quite frankly i always disregard his opinion on films because he just seems to like being the one that goes against popular thinking purely for the sake of it, and i think he decided that he was going to hate it before seeing it.
Overall though i thought it was a great adaptation, and very faithful to the source material.