It is amazing how fast you are in making reality out of an idea!
As a suggestion, if you want to display just the social network you might want to strip off some subscriptions. For example, my subscription export (visible at http://del.icio.us/inbox/phauly) is
- */trashware #pages tagged by everyone as trashware
- cshirky #pages tagged by cshirky
- ethanz
- joi_ito
- zephoria/academia #pages tagged by zephoria as academia

Based on this, we can say that my outgoing social edges are {cshirky, ethanz, joi_ito, zephoria}. So the idea is to remove subscription that start with "*/" and to extract the substring until the first "/"

I'm sure you are going to write it in perl in less than 20 characters!!! and less than 12 seconds ;-)))

The second part it already does (stripping anything after the slash) - your last subscription hasn't showed up yet because (I think) you just added it and I'm caching the pages for 24hr.

The first part (asterisks) I left in on purpose, just because it's interesting to see when people subscribe to the same general purpose tag as well (so yes, it's not just a social network).

You are listed in the Absolutely Del.icio.us Tools Collection.
http://pchere.blogspot.com/2005/02/absolutely-delicious-complete-tool.html