it's been discussed in interviews with Microsoft officials. you can plug the 360 into the hdmi in or any other hdmi device there.
Q: can you please clarify how the HDMI input is going to be used? Is it going to allow input from a set-top cable box or other HDMI devices such as Windows PC as well? Will the current Xbox 360 be able to input into the Xbox One to allow the UI of the One to be overlaid on current gen Xbox 360 games?
MN: so the answer is, “Yes.” First of all, it’s the only console right now that has HDMI in. And it’s going to absolutely allow you to plug in, for example, your cable set-top box and what that allows you to do… I want to make sure people understand this because it’s heavy. Is that when you plug it in, you’re going to be watching TV through your cable provider, through your satellite provider and then instantly you’re going to get that game invite to play Ryse. Boom. It switches like this. It’s like instant. So that’s one thing. And if you’re done with Ryse, you can go back to watching television. We also have this concept of overlaying a guide. So there’s a guide that can happen that we produce on the Xbox side that would kind of put over the existing guide so you can go up and down and manage it that way. Now we’re not a DVR. We have a game DVR but we’re not a true DVR in that sense. That’s going to be handled by your set-top box. We’re just allowing people to still watch TV… the types of TV that they have and then get back to their game experience and still stay connected to Live. How would you like to be watching your favorite TV show that’s not available anywhere else, but still get friend invites, right? And still stay connected. Or maybe even use our Snap mode and watch TV over here on the left while you're playing a single player game over here on the right. So think about that.
And the other question, you can certainly plug an Xbox 360 in the back of that. That was one of my first questions when I heard about the feature so there’s a lot of things we can do with that. Again it opens up great opportunities to have this great gaming experience but still stay connected.