I was surprised about how well the movie was done in regards to keeping to the story line of the book. In truth, I didn't feel it needed the big fight at the end, the essence that is Harry Potter and the Half-Blood Prince was really captured in the movie. It wasn't, by any means, a bad movie, I really enjoyed it. The emotion was captured beautifully, and the emotion was more necessary than every part of the book be crammed into the movie. The costume design could have been a touch better, in my opinion, (Draco looked like a vicar/priest/deacon through a lot of it, and Harry looked just plain sloppy) but in light of that, it doesn't matter in the grand scheme of things.