I finally saw it this evening and I'm really surprised that I actually loved it. I love the books and I was sure that I would be spotting every little difference. I did notice them but they didn't seem to matter to me.
First the things I didn't like.
* Harry flirting with the waitress.
* Dumbledore asking Harry about the waitress and then about Hermione.
* The whole Harry/Ginny relationship. I liked it in the book and love them together but they just spoilt it in the film.
Now the good.
* Lavender Brown was just so funny. I really enjoyed all her scenes.
* Cormac McLaggen was great. I loved it when he was licking his fingers whilst looking at Hermione.
* Harry under the influence of Felix. That was just so good and I didn't mind that it effected him differently to the book as the way it was portrayed made up for it.
* Both Tom Riddles. They were really creepy.
* Luna and her hat and sleepwalking.
* The part after Dumbledore died and they all raised their wanRAB to get rid of the Dark Mark. It brought a tear to my eye.
* Poisoned Ron and him falling off the sofa.
* Hermione telling Harry that he is an idiot for thinking he is going to be able to do it by himself and them watching Fawkes fly off.
I didn't jump when the inferi came out the lake because I knew it was coming. My friend (who hasn't read the books) almost jumped out of her skin though which was quite funny.
I had one *gasp* moment though which I don't think anyone has mentioned (correct me if I'm wrong as I've only skimmed the thread). When Harry touched the ring and then did the thing with his neck that Voldy does. I thought that was really well done and it planted a big hint for the end of DH. Then when Dumbledore said he thought he had found another Horcrux I'm sure he wasn't talking about the locket at first
I really enjoyed it (except for Harry/Ginny) and I think going in with low expectations helped.