The controller is the standard XBOX 360 wireless controller. The box contains a wireless controller hub. Supposedly, up to four controllers can be connected to a PC through this hub (though I presume not many games will let you use this feature). I have not tested connectivity for more than one controller at a time.
There are no apparent problems with this, on this Windows 7 64-bit Home Premium install. Plugged the hub into a USB port in the back, pressed the center button on the controller, and ready to go. Works great in Grand Theft Auto 4 (driving much much easier this way).
Can't wait to use this for DiRT3, yeah

The software is nothing special. In fact, beyond the standard joystick control panel, there is nothing else. You can test the functionality of the buttons, D-pad, analog sticks etc. And that's it. Would be cool if the software would allow programming of the buttons, or let you assign macros to the buttons like Intellitype for instance. Logitech does a much better job!
But I will not complain... the hardware is top notch and works great... and wirelessly.

If you already own an xbox 360, try to get only the wireless hub.