Earlier today, Xbox users started reporting issues with their Xbox One consoles not booting properly, ultimately stalling out at a "black screen" without ever loading. Per the twitter feed below, and also confirmed by Xbox VP Mike Ybarra, the issue has been identified and is in progress to be resolved, but has been going on for over two hours now.
From reading about the issue, not only did it bring most Xbox One's to their knees, it extends to Xbox Live and appears to have been a deployment that went awry. Once the issue is officially resolved, we will update this post, but you will likely need to reboot your Xbox One at that point.
[UPDATE: DAN} As of 3:20PM EST, the issues should have been resolved.