Josh Kirschenbaum has some interesting ideas about a different way to constructing a social network.
Instead of a LinkedIn (or any other system) style of listing everyone I know, and everyone who knows who I know- it shows a list of other nodes that I am strongly connected to. This strength is based on the quality and quantity of "connection" to that node. The node could be another person, or it could be a website/weblog/asset. This way, my "network" is a constantly evolving dynamic representation of my digital presence. Now if you expand this out- my "network" can determine other "likely" nodes to connect to based on how well connected THOSE nodes are connected to nodes I am connected to.
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