This was my favorite Harry Potter book, and the adaption of the film didn't disappoint me. I was nervous that this film (after the mess that was the Prisoner of Azkaban) would be a disaster, but was happily surprised at how much I liked it.
Plot: The plot was written by J.K. Rowling, so I really have nothing negative to say. It's interesting, fast-moving and the intertwining plot deepens with each film. I loved this story, and have everything good to say about it.
Acting: Were you expecting Academy awards? Of course not. But come on; it's Harry Potter! The acting was substantial, and with an added bonus: Robert Pattinson!
Music: One of the best soundtracks. I thought the music was very unique, and fit with whatever was on-screen without being distracting. The songs with vocals were a nice bonus!
Overall: I think the reason this movie wasn't very popular was because this is where the story begins to darken, and it only gets darker from here. However, I thought the film did a very good job of portraying the evil of Voldemort and his followers without taking away from the overall magic of the franchise. This one was a winner to me.