It sounds like a great potter "movie" but it will make the potter freaks pissed off.
It's a good (and short, for potter movies it is the shortest yet from the longest book no less) movie I hear with a biiig focus on action. A LOT of the book has been cut out. Gary Oldman has been reduced to a glorified cameo (who uh you know what has happen to him) as has Snape, both major players in the book version of 5.