Good for you Microsoft. The company has decided to use an actual USB port for their Xbox 360 controller, so you can use it on the 360 or your PC without any hassles. And of course, Microsoft will sell individual controllers for Windows for just $40 a pop (including driver). However, if you want to use the controller you got with the 360 for your PC, just download the XP drivers from Windows Update. So simple! Developers are lovin' this idea and backers include EA, Ubisoft and THQ.
Xbox 360 USB Controller to Go Cross-Platform [Everything USB]