If you haven't read the book yet, get cracking.
Not much needs to be said for this one. The book series has sold 400 million. The movies have raked in more than five billion worldwide. If The Order of the Phoenix could be pared down to one book, chances are Deathly Hallows could have done fine with a three-hour run time. Lots of orchestration, lots of shots with Harry and Voldemort and lots of talk about the movie being part of a generation-defining event. Ladies and gentlemen, the likely box office champ of 2010.