They changed or left out quite a few things from the book that I liked. Most of those changes seemed to sacrifice secondary character development without adding anything important to the flow of the movie.

There was nothing about Neville and Ginny's rebellious activities at Hogwarts during the year. The scene of Harry going to Ravenclaw tower and finding out about the diadem, the scene where Neville kills the snake, and the scene where Ron and Hermione finally kiss were all altered heavily, to little effect. Also, the fight between Voldemort and Kingsley, McGonagall, and Slughorn was missing. Another missing moment was that Harry did not repair his original wand with the Elder Wand.

Like most of these adaptations, the people doing the adapting seem to have missed the trees for the forest, capturing the broad strokes but not the little details that really bring the novels together. It was enjoyable enough, but it could have been better. I give it 3.5 stars.