Watch this demo. Ignore the silliness and focus on the quality and content of the demo. To me, this is a huge step forward in bringing forward thinking technologies from the lab and niche apps into the mainstream. The interesting stuff comes in at about 1:20. The app is called Playroom and is built-in to the PS4. The down side is that it requires the PS4 camera (a $60 add-on).
The cynics among you will dismiss this as a ploy to sell the camera (the Xbox One equivalent is included in the box). Perhaps. But no matter the motive, this is still some mighty cool tech.