Once you regard the group mind as part of the environment in which the software runs, though, a universe of un-tried experimentation opens up. A social inventory of even relatively ancient tools like mailing lists reveals a wealth of untested models. There is no guarantee that any given experiment will prove effective, of course. The feedback loops of social life always produce unpredictable effects. Anyone seduced by the idea of social perfectibility or total control will be sorely disappointed, because users regularly reject attempts to affect or alter their behavior, whether by gaming the system or abandoning it.
But given the breadth and simplicity of potential experiments, the ease of collecting user feedback, and most importantly the importance users place on social software, even a few successful improvements, simple and iterative though they may be, can create disproportionate value, as they have done with Craigslist and Slashdot, and as they doubtless will with other such experiments.