It's funny reading the comments, a lot of people are saying that he's going to make his parents lose their jobs.

Only thing I don't like is the tiles. There's not really any distinction between them.

Looks very functional but certainly not very splashy. Maybe they'll improve the aesthetics of it before release.

How did this person get an Xbox One so early without being a dev?I like the interface a lot, I hope you can customize the tiles and swap in some or swap some out that would be pretty cool.

No vid for me.. Apparently it had been deleted, if someone could embed a second link I would be grateful.

Looks like the user deleted the video. Good thing someone else copied the video and posted it.

He's probably a beta tester. That's why he has access to the betas. The tiles can be customized, you can pin anything you want on the left side. It's just like W8/WP8 in design.

Probably because it isn't final hardware but there was some serious input lag.

I'm guessing it didn't pause because it was on a part of the game that didn't allow controller input.  Later, when he did, the game paused.

Likely he's a family member of an employee at Microsoft.

Employees within the Xbox Team, possibly now outside of it, have the Xbox One beta units.  They've actually had them for a while.

You'd also be surprised how many employee's kids do this.  It happens at least once every time Microsoft has a beta.  Maybe not a video, but someone's kid posts something online somewhere.