Adaptation is difficult but writing from scratch like jackson did is a little difficult than that
Anyway, turkish critics say that peter jackson followed the story in the book and bacause of this (also second book's story is weak they say) second movie is boring and not better than the first movie. Well, I never listen them and their silly, crappy ideas, but I totally disagree that he followed the story more than the first movie
I hope that no one will make the movie of Silmarillion! :rolleyes: