Michel,
Thanks for the reply. I did not realize how many third party products rely on UPnP. It would, however, be nice to have the ability to disable it after the ISY has been discovered. I'm assuming UPnP is only used for the initial discovery of the ISY. I'm also assuming the IP address of the ISY is then used for any further communication.
I appreciate the fact that I may be an odd case, but I transfer a lot of large files wirelessly using my laptop. So any broadcasts that I can eliminate from my wireless network will only help improve my transfer rates. Sure, I could firewall the UPnP ports from my wireless side, but to me, it's much cleaner to just disable it all together!
Thanks again!
PS - I love my ISY. It just works!