"Any application can be snapped to a game," Penello said, according to GameSpot. "This could be the live TV feed, so if you wanted to be playing Ryse and Killzone at the same time, you could snap that."
Killzone, of course, is a PS4 game. That means you can use the Xbox One's multi-tasking features to switch back and forth between both consoles' games. If they're hooked up.
So what else does this mean for you? Say you want to capture PS4 gameplay on a device like the Elgato—a feature that won't be supported at launch, according to Sony's Shuhei Yoshida. Hypothetically, you could plug the Elgato into your Xbox One and capture gameplay from that feed instead.
And what about your Xbox 360? Or your Wii U? The possibilities are pretty interesting.
Your Xbox One And PS4 Can Hook Up