One thing I haven't seen anyone mention is the fact that everyone in the DA got the cruel quill treatment. That's a huge change, in my opinion, as it was something Harry was so insistent on not sharing with anyone. And I don't see a real reason for it in the movie, except to make everyone feel sorry for the boy (Rigel? Nigel?).
Um, it wasn't in the book, right? *goes to check*
In other news, my little girl can say "Harry Potter," although it sounds more like "heh pahhh". It still cracks me up.