The gnutella client needs a place to start - somebody to connect to. The hosts that it connects to when first started are simply helpful sites that have made a list of recently active gnutella servents for your servent to try. Once the sites have given your servent a list of other servents, and hopefully added yours to their list, your servent disconnects from the host and is off and running on it's own.

Obviously, these "kick start" sites are potential targets for the RIAA. If that were to happen, other strategies for getting a startup servent list would have to be investigated. My guess is that the RIAA will come gunning for these sites as soon as Napster is killed.

Of course, starting a lawsuit, and winning one are two different things and it appears that the legal standing against these hosts is pretty slim.