Microsoft's head of Xbox, Phil Spencer, has confirmed through a short Twitter conversation that the Xbox One will soon get keyboard and mouse support, possibly for finer control while playing games.
Spencer confirmed keyboard and mouse support for the Xbox One after a Twitter user asked about game streaming from a PC to the Xbox, which would require keyboard and mouse support to function correctly. While Spencer said that there are currently no plans to introduce Windows 10 to Xbox One streaming, keyboard and mouse support "aren't far away".
The Xbox One already supports keyboards for basic text input, so the only feature Microsoft needs to integrate is mouse support. Considering the Xbox One runs a modified version of Windows, and the console will be updated to a variant of Windows 10 in the near future, it shouldn't be that hard to code in support for the versatile peripheral.
What isn't clear at this stage is how the Xbox One will support keyboards and mice. It's possible that Microsoft will just introduce support for these input devices to browse the interface and access Universal Apps, although there's a chance we'll see games support keyboards and mice as well.
Microsoft has already announced an Elite Wireless Controller for the Xbox One that has added functionality for pro-level gamers, so the next logical step would be to introduce keyboard and mouse support in games for PC-like precision. Many of the games on Xbox One are also available on PC, so again it wouldn't be hard to introduce support for new input devices on upcoming titles.
With only a little bit of information to go on at this stage, we'll just have to wait and see what Microsoft's plans for Xbox One mouse and keyboard support are. A Windows 10 on Xbox One beta is scheduled for "post-summer", so that's where we might see support first introduced.