Oh it's lovely. Casting Alan Rickman saves it from the big flaw of the book, which is that it seems a bit harsh to fob a teenaged Marianne off with an old bloke who happens to have a crush on her. If the old bloke is actually Alan Rickman, then suddenly I stop feeling sorry for Marianne.
Off topic, is anyone else looking forward to Snape's big scenes in the last Harry Potter film rather too much?