If you own an Xbox One, your controller can now serve double duty as a PC gamepad. Microsoft's Larry Hryb, a.k.a. Major Nelson, posted download links to official drivers for the controller on his blog this morning.
The installation process sounds simple: just grab the appropriate 32- or 64-bit driver, connect the controller to your PC with a micro-USB cable, and you're in business. The controller is compatible with any game that supports the Xbox 360 gamepad. According to Hryb, the drivers will be part of an upcoming Windows update—but if you need them today, we see no reason to wait.
Currently, it looks like the controller works in wired mode only. This VentureBeat article says the Xbox One controller uses a different wireless protocol than the Xbox 360 controller, so the existing wireless adapter won't work. Microsoft has offered no indication of when a new wireless adapter might arrive.
The Xbox One controller is supposed to include 40 improvements over its predecessor, including higher-precision thumbsticks and a crisper d-pad.