Xbox 360 will be launched with two different controllers, one wireless and one regular. Which you chose depends on need and budget, but the regular wired controller has a big plus. The controller can namely be used with a Windows PC and Microsoft has actually already launched the Windows-version of the Xbox 360 controller. Considering the positive judgments Xbox 360’s controller has received from the press this may very well be a very ingenious move by Microsoft.
At ExtremeTech they’ve tested the PC-version of the controller which you can buy today, the only thing that is different from the console version is that you get a Windows-driver in the package. According to ExtremeTech’s review it seems that Microsoft have a winner.