Whether it's open source or not has nothing to do with it, the protocol is open source, at least I'm assuming, I'm not the most familiar person on the planet with gnutella.

milhouse_ph,
For me it's the exact opposite, I listen to the most obscure genres of music there are, and I can't find ANY of it on said clients. Granted, chat isn't the most important thing, but I think list browsing was, it was the number one way I discovered new music. By finding who has a certain band, then browsing their list for similar music I may not know of... I won't even use a client that doesn't have that capability.
WinMX (not gnutella), has these abilities, and is decentralized... however it doesn't have no where near enough users, so again, I can't find any music of interest.
IMO, there isn't a client out there that is nearly as good as Napster was. Also, I used Napster in conjunction with audioGnome, so I had much more functionality than the Napster client on the network.