I won't give any spoilers, but I will tell you that the movie clearly relates what is a fairly complicated set of relationships, and that's not always easy. I think that is what made past movie attempts difficult. The audience sometimes couldn't follow all the details, and the plot became murky. Not this time.
Doug is an avid Dune fan, having read the books. He tells me that the movie is true to the book, in as much as it relayed the story faithfully. He told me it did glaze over a few details, but he felt it did so appropriately - keeping enough to maintain the story and only dropping details that might have made things murky when portrayed in a movie format.