During a livestream on Monday, Xbox head Phil Spence announced that the new revamped Xbox One dashboard and Xbox 360 backwards compatibility will drop on November 12th, according to Polygon. The update will go out to all Xbox One owners.
The new interface, also known as the New Xbox One Experience, and support for the backwards compatibility has been available since September as part of the Microsoft preview program.
Microsoft promises that the new user interface will be faster and improve the ease-of-use (not that the interface is that difficult but it looks a bit more like Windows 8 tiles, as well as tighter integration with Windows 10.
Microsoft promises that more than 100 Xbox 360 games will be playable at launch through backwards compatibility. Which is interesting because Sony has had their PlayStation Now out since the beginning of the year and they only boast the same amount. You can check out the current list of supported games here.