They kept much of what was in the last book, but did keep out alot as well, course if they were to put in everything the movie would have been something like 10hrs long and took 10 years to make.
I have read half the book and I have to say AWSOME job bringing it to the big screen. Only a few things were changed but for the most part things have stayed true to the book, which is always great. If you could get past all the immature screaming girls, go see this at the latest possible showing cerfew people cerfew. Buy your tickets on line and definatly enjoy. Oh just a hint they bring more to the vampire myth in this story.