Disney took the curtain off it at Con last weekend. Steven Lisberger returned to write the story, though not the screenplay nor to direct. Joseph Kosinski is directing, he's also doing the Logan's Run remake (where they've apparently dropped the Carousel age from 30 to 21?!) Jeff Bridges returns as Kevin Flynn, and Garrett Hedlund (Friday Night Lights, Four Brothers) as his son Sean. No word on whether any of the rest of the original cast will return in any capacity.
IFC has footage from the panel