To my previous posts on visualizing social networks (see here, here, and here), let me add the coolest visual network site I have seen yet. Behold musicplasma:
Thanks to spinster for alerting me to musicplasma (and OSN2005 for cluing me in to spinster).
As spinster so rightly points out, there is serious potential synergy between network visualization tools and collective filters (such as LastFM in this case; see also social bookmarks). For example, suppose I could inform musicplasma that as much as I love Chick Corea, I am not a Pat Metheny fan. And then suppose musicplasma could update the visual network to suggest not just who is related to whom, but where my interests are likely to fit in with that network.