The Washington Post has a short new interview with Alfonso Cuarón in which he discusses how hard it was to direct Harry Potter and the Prisoner of Azkaban as well as how scary the movie is.
WP:The movie is rated PG-13. How scary is it?
Cuarón: The books are quite scary, but at the same time you are in a universe of make-believe that in a way is a gentle scary, it's not really trying to test your limits. . . . Ultimately there is a light through the darkness. I think to honor the spirit of the books we cannot say, 'We have young kids [watching] so even though the book has a werewolf, let's skip the werewolf.' . . . It's scary but it's not violent. Also, the movies have to grow along with the books. The readers are getting older.
WP: What was the hardest part of directing HP3?
Cuarón: My challenge was not to disappoint the fans, but on the other hand, to make a movie that if you haven't seen the other Harry Potter movies, or read the books, you can watch it and understand.