Okay, so I figured out what was happening with my wife's Rio. It was picking it up and it couldn't find a proper device for it (according to /var/log/messages) so it was assigning it usb-storage. Now I want to use usb-storage for other things. So I don't want to blacklist it (which is what I did temporarily to get it to work under VMWare's guest OS). It seems to me there should be a way to look at the device ID as identified in /var/log/messages and to tell the hotplugging system to treat a device with that ID like X. How do I do that? And how do I (in the process) basically get it to ignore said device? Any help would be appreciated. Preston