It has been over three years since Microsoft originally promised mouse and keyboard support for the Xbox One. A year after in 2016, Xbox chief Phil Spencer said that it was months away. Another year after that, Corporate VP Mike Ybarra said that games with mouse and keyboard support were coming soon.
Fast forward today, yet another year later (we do seem to get yearly updates on this). Microsoft announced that mouse and keyboard support for the Xbox One will be live for select Insiders in the coming weeks. The firm partnered with Razer for the first mice and keyboards, something that's been rumored for months. Microsoft did say that most USB and Bluetooth mice and keyboards will work, but it's partnering with Razer for the best experience.
The feature won't be available for all games though. It's entirely up to developers to decide if they want to include mouse and keyboard support, and how they're going to do it. This is meant to make sure that games are still "fun, fair, and correctly balanced", as a keyboard can provide an advantage to users in some games.
Microsoft said that the November 10 episode of Inside Xbox will have more information about its partnership with Razer, although it didn't say if hardware will be shown off. It will, however, announce games that will support it. One of the first games to support the feature will be Warframe.