I saw the movie Sunday afternoon and it is pretty good. There are folks who can point out a quibble here and there, but I didn't find anything jarring. Or at least nothing that bugged me that didn't bug me in the book. If you've been pondering seeing the movie, I recommend you do go see it, and stay for a bit after the credits start rolling.
( Just in case you're leery of spoilers )
One thing I really liked was that C.S. Lewis, unlike most, has centaurs on the side of the good guys.