Tadao Technologies is in the process of making their boards usb 2.0 and a mini-b usb compatible. As of now, the prototypes work with Mac OSX and Windows XP and Vista. Alternate boot screens, saved settings, and diagnostic downloads will be availble with the USB interface. Current Yakuza boards will not be able to be upgraded to use usb.
This thought of using a usb interface is pretty cool and could be very handy for a lot of players but the only thing that isn’t cool is that their is no interface for linux users.