Interesting reading: some have been asking what the cost of moving from a
peer-to-peer to a service/consumer model are, in terms of applications
deployed and the ability to build more robust business models. Many ISPs
are thinking in terms of VoIP as a next generation business, the one after
"selling bandwidth". But there are issues with that as well...
http://www.fourmilab.ch/speakfree/eol/