Dune is one of the greatest audiobook experiences I've ever had so I would definitely say if you have plans to watch the upcoming HBO film by the same name then do yourself the favor and listen to the audiobook first. You have plenty of time too as Dune the film doesn't come out until October.
I have lots of faith in Villenueve and am very excited to see his take, but there is only so much story you can fit into a single movie.
You're absolutely right. I actually suggested someone watch David Lynch's Dune before they see the new one a couple days ago. But I don't think that's nearly going to cut it. Dune has one of the most complicated stories I've ever seen. All the different characters and planets make it super hard to follow. The best thing to do is to read the book or listen to the audio book before you see the new movie. I also have faith in Dennis Villeneuve to give us a solid and understandable movie though. He did it with a somewhat complicated movie with Blade Runner already. I think he'll do it again.