The movie was entertaining, but I felt it was unnecessarily too PG. I was annoyed that the script writers deviated too much from the book by inserting dialog and scenes that were not supposed to be there. HP & the Half Blood Prince had many funny adolecent scenes which seemed to drive the movie. The feel and sense of urgency that a wizarding war was commencing wasn't really felt.
As usual the actors were brilliant, but the only dark feeling I was left with was the actual lighting used.