Oh, right, I saw a movie tonight. :) It rocked. The first year of Harry Potter that I read first before seeing the movie. It was last summer that I read it, so I had forgotten many parts, but they quickly came back to me on screen. I don't remember for sure, but I thought the book had more classroom scenes having little to do with the plot. If so, they left them out of the movie, surely to keep the length reasonable.
I loved all the virtual camera tricks (flying through glass, mirrors, tight spaces, etc.) - none of it gratuitous, of course. :) Direction and everything was well-done. I remember reading last year how the new director had decided to show the kids more in street clothes than formal robes. I thought that would be a big difference, but I really didn't notice... except that it seems they designed Hermione's outfits to reveal her... *ehem* growing up. But on the other hand that's how most girls her age dress these days anyway so I can't blame them for being accurate with their goal.
It seems like they hardly explained anything though. The first two movies did a good job of explaining stuff to people who hadn't read the books. But I have a feeling if I didn't read the book for this one I'd be scratching my head a lot during the movie. To put it another way, if normal movies bring the audience in by relating to life as we all know it, this movie brings the audience in by relating to life at Hogwarts. Unlike the books that always seem to design the first chapter to re-introduce the characters, I guess they decided to make the movie expect you to have seen the previous movies first.
But regardless of all my thoughts on the matter, the movie worked very well for me, and that's all I should care about, right? :)