In theory Dune should have been a failure. Filmed in quite an abrupt manner, it's a mess of ideas, plot and imagery that requires background reading to make sense of. But of course that's not necessarily asking for much, and since I have read the initial trilogy I rather liked the movie.
I didn't like the book. It was muddled, badly constructed and failed in its promise to deliver. I also thought back then that a well reasoned movie could easily fix all the issues I had with the book, and it turns out that that's what happened. The movie introduces a purpose and pacing that clears up some of the flaws with the storytelling of the novel, and the story and universe are all the better for it.
That said, it wasn't a perfect film. Continuing the ironic relationship between it and the source material, I don't think I would have understood much of the film without having already had the story told to me. And as previously mentioned editing seemed a little rushed, with the acting merely doing the job. Special effects were of a decent quality.
Perhaps then it seems that this movie reinforces what we may already have known - that the Dune universe is bigger than just a book and movie, and that you really need to consume it in multiple forms to really get the most from it. And when you do, it's all pretty good.