Microsoft has made it clear that Xbox One is designed to be laid horizontally, but you can be sure that some gamers will position it on its side anyway. For those who like to break the rules, just know that you're doing it at your own risk.
According to senior director of product management, Albert Penello, the device simply wasn't designed to be positioned upright. It doesn't have anything to do with cooling, rather, the disc drive was built with a specific orientation in mind.
"We don't support vertical orientation; do it at your own risk," he told GameSpot at Tokyo Game Show. "It wouldn't be a cooling problem, we just didn't design the drive for vertical. Because it's a slot loading drive, we just didn't design it for both."
Do you plan to throw caution to the wind, or will you be playing it safe and heed Microsoft's warning? It sure would be a shame to end up with scratched game discs. Then again, you could always go digital-only...