Originally Posted by Brad Gosse

The difference between p2p apps is simple. Some access one network ie: kazaa=fasttrack and limewire=gnutella.

Additionally there are p2p apps ie: Morpheus and Shareazaa which access more than one network.

I can't comment on the spreading factor of the files because I am not sure what you mean exactly. Feel free to ask in more detail and I will do my best to attack the question for you ;)