Xbox One Alpha Insiders get 1080p support and one hour of recording time through Xbox DVR.

In the recent Alpha build released yesterday for the members, the preview team at Xbox has enabled FULL HD support to all Xbox One consoles through Xbox DVR. Later this year with Xbox One X, gamers will be able to record in 4K@60FPS.
Here are the new features available in the build 1710.170910-1900:
• Game DVR
Capture at 1080p, and capture directly to an external drive.
Another feature not mentioned in this build’s patch notes is the increased recording time now for one hour using an external hard drive. Thanks to a Reddit user for capturing a screenshot:

These features should go LIVE later this year for the general public, but for now, they’re limited to Xbox preview members.