I thought the acting in this Harry Potter movie was the best I have seen in any of them. The movie was very entertaining -- a lot of humor this time. I also thought it was probably easier to follow for someone who hadn't read the book than many of the other recent ones were -- it flowed very nicely from one scene to the next.
My daughter and friend didn't like it because there wasn't enough "action." But I should point out that they haven't liked any of the movies on 1st viewing since so much of the book must be left out, yet they have grown to love all of the movies.