It doesn't seem that long ago, but the first Barcamp Amsterdam was way back in October 2005, where RalphM and I first schemed about Jabber World Domination. But in reality, a lot of time has passed -- Jabber is now called XMPP, there have been many more Barcamps outside of the US (yes, Amsterdam was first! picture from Ton's Flickr pictures), and we've got a ton of interesting identity and social software standards / formats / tools to start integrating.
Ralph did a workshop on Federated Social Networks at the beginning of December, which I unfortunately wasn't able to attend on short notice. Now Ralph has set the date for a follow up event to be held along with Barcamp Amsterdam III on March 1st and 2nd.
I will, unfortunately, once again be missing the event, since Drupalcon Boston 2008 will be happening at the same time. I'm hoping that some co-conspirators on a couple of projects will be able to attend (I'm looking at you and you).
I suspect the technology stack that will be discussed includes DiSo, OpenID, OpenID Attribute Exchange, and OAuth, so anyone interested in those items and how they relate to social networks should plan to attend. Note: although I have a reputation as a handwaver supreme, this will most likely be a down and dirty technology, specs, and implementation discussion at its core, so pack your developers and throw them into the capable hands of RalphM.
Lastly, look to the Four Kitchens GetOpenID.com announcement and the work that the Drupal community has already done around OpenID to be the basis for compatible work around this. We'll likely have a scrum around this in Boston.