I'm running the normal Droid Razr with ICS, and I can't even (haven't played much yet though) to get my Windows 8 Enterprise system to recognize the phone when I plug in the USB. The phone senses it's charging; however, when I go to the tethering & mobile hotspot options, the phone also states USZB not connected
I sent an email to Motorola and this is the reply I received from them a couple day s ago.
Even though as of the moment we don't have prior information as to when the option for windows 8 tethering is available, I will forward your feedback to our software developers and engineers and hopefully they will find a resolution for this.