Move-like motion controller instead of traditional gamepad got a little slimmer, thanks to an interview with Sony R&D wizard Dr. Richard Marks. "I said that pretty much from the beginning that we're not trying to get rid of the gamepad," he told Gamasutra, saying of the idea that Sony might go motion-only for PS4: "I don't think that makes sense."
"The gamepad is a really good abstract device," Marks explained. "It can map to so many different things. It doesn't map one-to-one to those things, but it doesn't need to for a lot of game experiences."
Of course, Marks is no doubt tinkering on some future iteration of the Move technology, but there's one gameplay interface he apparently has no interest in exploring: brain waves. "I think the brain interface thing is too far," he admitted when the topic was broached. "When you play some of the experiences like Rock Band where you break into a sweat playing the drums, those things are good. I like those things. I don't want to remove all of that."