This is not Harry Potter and the Prisoner of Azkaban.
This is the movie Harry Potter and the prisoner of Azkaban, which in some places rocks so much more then the book yet in others it's a bit ... uh ... what?
I'm thinking the DVD release is maybe an extra 35 minutes long at least (but then I thought that of HP1 & Hp2)
But aye, good bits;
* Angst free Harry!
He started getting a little angsty in this book there's none of it here, woot!
* Smarter people!!
The characters appear to be cleverer in general not doing somethings that were maybe a little silly in the book.
* Pro-active Hermonine!
She punches, she throws things!! It's like a mini-action movie! Woo!!
* Ron should _NOT_ be comedy relief
Bad movie makers! Naughty movie makers, back to film school with you!!
* Plot comet!!
What's that, oh I need to explain this well *BOOOM* but hey in the book that was nice and thought out well and ... bah.
So yeah I'd say this is a good movie but if you want to watch it properly the book is really essential pre-reading otherwise you will probably miss quite a bit.