He kept all the magic thingies and even added an element that was not present in the books with the random female voice/voices "speaking prophecies" to Paul. But more importantly, he ruined a main character, transforming her into basically a contemporary American. It might be well paced, it might be pretty, but it's not Dune and it doesn't make as much sense as it should have had they not messed with it for the sake of larger audiences.