I think it must be because I've never been a fan of canon that I love the movies. I don't care if Hermione wears pink or epilogue!Draco looks like someone's grandfather. I also don't care that the Burrow inexplicably burned down in the last movie. I mean, it was odd, but whatever.
I think that death scene is going to kill me. I'm not a visual person but Snape's death in the books was painful to read. I can't even imagine how much worse it will be to watch on the big screen. Especially with such a talented actor as Alan Rickman in the role.