They left out a lot of detail skimming just enough detail for someone who has not read the book but is paying close attention to the movie to get the idea of what is going on. They did a good job of creating visuals of some interesting creatures but only the imagination can do justice to retrieving the Horcrux. The story was rushed but there's a lot of material in the book to cover in 2.5 hours. Given they only had 2.5 hours it was a great job. I'd go see it again.