I am a huge fan of Dune and think it to be a literary masterpiece. I was very saddened to see the plot butchered by the director.
Many of the book's best scenes were deeply altered or removed altogether on the movie. The meaning of entire scenes and the mystery surrounding the conspiracy against the Atreides, as well as the real role of multiple characters, and the transformation of Paul into Muad'dib were so modified that the whole thing becomes not more than any other unimpressive sci-fi action movie.
Good screenplay and adaptation of the technologies and landscapes into the big screen, if anything can be said positively about it.
Big disappointment.