I suspect that most of the value generation from having a single shared conversational locus is not captured by the individual generating the value (I suspect there is much distributed value from having “a conversation” with better structural integrity / more coherence, but that the value created thereby is pretty distributed). Insofar as there are “externalized benefits” to be had by blogging/commenting/reading from a common platform, it may make sense to regard oneself as exercising civic virtue by doing so, and to deliberately do so as one of the uses of one’s “make the world better” effort. (At least if we can build up toward in fact having a single locus.)
Brian Tomasik’s article Why I Prefer Public Conversations is relevant to