Well I have had viiv working spottily, and media center media sharing sort of working with both my hr20 and hr 21. However-then my pc started "slowing down" or hanging it appeared. Turned out this is a known problem with XP SSDP discovery service which viiv and windows media sharing need to run. SSDP keeps searching and hangs explorer. If you turn off SSDP-hangs go away. But turning off SSDP turns off viiv and windows media sharing and closes those firewall ports. So should I just punt to Tversity? Or I see posts up here which seem to indicate that if I use static IPs for my DTV boxes, and i open the ports in the firewall myself-I don't need UpnP?