Hi,
I created a small document, which describes Gnutella in the well known friend of a friend model, and documents the changes of the network over the past few years in the same easy-to-read-style.
It should be technically correct, while not diving to deep into technical issues.
The document-format is a wiki, so you can correct errors and add new information (but please stick to the non-technical style).
You can find it here:
http://gnufu.net
Best Wishes!
Arne Bab.