[TheFluff]

Uh. The point of Share, Winny and (presumably) Perfect Dark is that they are all true peer-to-peer networks with no central controlling server (like, for example, a BT tracker). The list of nodes is just a list of other peers in the network. Once you are connected to just one peer/node to start off with, the client will get lists of other peers/nodes/whatever to connect to from that peer. Hence you only really need the online nodelist once; the first time you set up the program, so it can "bootstrap" itself into the network. To compare with BT: every client is also a tracker. If the client didn't exchange network info with other clients, you'd have Direct Connect except with no hubs, no file lists and no usernames, only hashes. Which would be kinda useless.

tl;dr: you only need the nodelist to get in contact with someone who's already connected to the network; once you are connected to one node, your client will automagically find and connect to others.