A large German company wanted to introduce PLN hardware on a big scale here in Germany some 2 or 3 years ago, but they kept having problems and finally dropped it. I think they wanted to use it to offer an alternative to DSL internet connection, but it didn't quite work out. Too expensive, too unreliable devices - so they said
Now, with all the hype about BlueTooth and WLAN, it seems to be almost forgotten, although those adapters for home networking now exist, which is a good thing.
One aspect you forgot to mention is the additional security. No more Mr. Parasite parked in your front yard with a laptop and WLAN card, no more interesting chalk signs near your house ("those kids sure scribble odd symbols on the walls nowadays...") - perfect. Congrats!
