I'm about a fifth of the way through Goblet of Fire and thoroughly appalled at how much movie canon has sunk into my brain, to the detriment of book (i.e., real) canon. I almost forgot that Beauxbatons and Durmstraaaaang are really coed. And that's just one of many instances. Now I'm scared of what the movie version of HBP will do to my brain.
*goes to continue reclaiming grey matter for canon*
Incidentally, this is my first post via the LJ app for the iPhone. It's pretty useful, especially the shortcut keys for HTML code.