During today’s Inside Xbox livestream, Phil Spencer announced that mouse and keyboard support is coming to Xbox One.
It will be on Xbox Preview in October, and will be initially tested on Warframe. The idea behind mouse and keyboard support will be as a tool for developers, so they can choose how they want the control style integrated, if they want it integrated at all.
More information on mouse and keyboard support will be coming during the returning XO18 fan event in Mexico City on November 10. There is currently no news when this feature will be rolling out for all developers and gamers, but expect news along these lines during XO18, and for more on the exclusive Microsoft and Razer partnership for mouse and keyboard support.
Source: IGN.com Xbox Announces Mouse and Keyboard Support