This was an ok book, not as enjoyable as the first. I didn't find the story all that engaging. I liked that there were little clues littered all over the book and it all comes together by the end. The characters, however, leave much to be desired as they are flat and not fleshed out at all. Harry and his friends fit fairly neatly into common archetypes and the villains are petty and evil with no real explanation of their motivations. I listened to part of it as an audiobook, read by Jim Dale, who was okay I guess. Truthfully, I'm not all that impressed with him. Most of the voices he used for the characters were indistinguishable from one another, though there were a few good ones.
Also, I didn't realize that there were so many changes to the text in the American version of these books, like pitch (as in Quidditch pitch) to field, or mad to crazed, insane, wild, etc. I guess the British really like using the word mad far more than Americans.