At E3 last year, Microsoft announced Project Scorpio, which it says is the most powerful console ever, capable of supporting true 4K gaming. Little is still known about the device, and we'll likely hear more about it at this year's event.
But today, Project Scorpio has shown up on the Microsoft Store, although it doesn't really provide any additional information. There's still no pricing, or even a name; it's still listed by its codename. Instead, there's just a link to have the Store email you when it's available.
The listing does confirm that the console is coming this holiday season, and that it will be compatible with all Xbox One games and accessories. It will support "high-fidelity virtual reality", although this likely won't be a feature coming out of the box, as Microsoft has already said that mixed reality support is coming in 2018, as well as to the Xbox One and One S.
Microsoft's E3 2017 event is slated for June 11, so you can expect to have all of your questions answered then. If you want to sign up for email notifications, you can do so in the US store here, and in the UK store here (via On MSFT).