Jon Udell has an interesting discussion of social network software: That it will be subsumed into the general Internet over time. LinkedIN, for one thing, is now a fairly well closed off professional network, useful if you want to get in touch with someone at a particular company, and free of spammers, unless you count the headhunters with 5000+ connections. Incidentally, just like the early academic networks, back in the 80s.
The trouble with networks is keeping them at the right size and with the right nodes. When it grows to large, smaller groups will secede and form subnets, often with dimensions added to the connections between them. That’s the way it is with LinkedIN as well: It started off with very strict limitations on what you could do. Then, if you pay for the premium account, you can send emails that shortcircuits the chain of connections and ask questions that pop up on people’s home screens.
I have 287 connections on LinkedIN, and have been pretty stringent about keeping them to people I have actually interacted with, enough so that I would remember them. The network is useful, but the growing size of the overall network means that some sort of differentiated contact settings are needed. Eventually, LinkedIN will be too large to manage, the ratio of useful information to crap will fall, and people will ignore it, except for certain subnets, tightly interlinked and with many mutual recommendations. Just like the blogosphere three years ago, the Well in early days, and the various nets back in the 80s.
Hang on to you own website, I say. Manage it well. As long as the network management tools keep getting overwhelmed, make sure you node is polished, well lit, and carefully selective where its links goes.