Internet Service Providers don't like BitTorrent because it basically destroys their business model (flat rate access) and stresses the very part of their network most vulnerable to high usage (the upstream). Many ISPs simply limit the available bandwidth for BitTorrent traffic. Cable operators that now seem to include Comcast go a bit further and disupt the "seeding" process that allows BitTorrent peers to act as better upload nodes. In Canada, Cogeco and Rogers Cablesystems also "step on" BitTorrent traffic.
If P2P traffic keeps growing the way Cisco predicts, and if no changes are made in the dominant retail pricing model, throttling of P2P applications will happen on a wider scale. P2P attacks network capacity at its weakest link.
