Seeing actors take a character and make it their own, gives a different view of the characters we know from the book. Some, like Luna, may seem just as awesome. People may find themselves warming up to Bonnie's portrayl of Ginny. There will be those traumatized by movie!Hermione.
Honestly, for me I kind of view the movies as fanfiction/alternate canon, where things are...skewed. So I go in with different expectations. I kind of expect Draco to be even more of a caricature of himself than he is in the books. I always remember Dan's scene in Philosopher's Stone where Harry finds out that he's a wizard and thinking, "this dude really needs to learn how to act. Harry is so...flat.".
So, I wanted to ask y'all how your views of characters, relationships and hell, anything in the movies really compares with your personal views of book!canon.
OOTP movie spoilers are welcome - would be very interested in comparing changes and developments.