I just installed it on my Vista x64 machine, and it does indeed work. I haven't had time to experiment much with it, but I certainly recognised when I plugged a USB thumb drive into the DIR-655.
Does this mean I can actually connect a printer to it and remotely print to it from my network, even if my main machine is turned off (providing, of course, that the other machines have the shareport utility installed on them)?
Another question for the experts: is it in any way harmful to a thumb drive to keep it plugged into a USB port? Even when powering up/down?