According to Deadline, the Dune movie is dead for now:

Paramount has turned loose the giant worm, and everything else that was part of the seminal Frank Herbert science fiction novel series Dune. The studio’s four-year attempt to make a movie out of the franchise has fallen by the wayside. Paramount and the rights holders came to a parting of the ways as the rights lapsed. “Paramount’s option has expired and we couldn’t reach an agreement,” said Richard P. Rubinstein, who controls the rights to what is considered the biggest-selling science fiction book ever. “I’m going to look at my options, and whether I wind up taking the script we developed in turnaround, or start over, I’m not sure yet.”