There almost seems to be 2 ideas moving in this thread -
social networking
vs
member web pages or micro sites
I don't know exactly how our group might use social networking, as we already have tools such as a public bb w/ chat room feature, private messaging, etc in place and I don't really see moving off those platforms as they are pretty established an have a wealth of back data. Would be an issue of member only or public also. (They are a separate vendor from our current website and will not be impacted when we move to Wild Apricot).
However, the member web pages or micro sites, I could see used. We have had requests for members without websites to be able to post and control an individual page (pages) within our website. From a minimal just give basic info and contact for the public to be able to contact a juried member without a personal website to a more involved "mini-store" where they could post 10, 20, however many items for sale. This moves into e-commerce and mimics some of the art sights, which I could look up if anyone wanted the more specific example.
This 2nd part is a pain in the butt if the individual does not have access to those specific pages only for updating - who has time to update the site in general let alone individual's pages. But could be used to generate revenue for the non-profit.
Most of our juried members have websites and we provide a link to their site. Having the personal page available for members without a site would keep everything consistent and would be nice to have.
If "mini-stores" were available, we would find a way to put them to use - but we would want the monetary transactions for their sales being totally their own and not tied in any way to our organization. So it is a bigger project and a further out time line.