I've just listened to the discussion - and have found it very interesting.
Several thoughts came to mind, some of which others brought up ... others that I thought at the time I heard, would have commented via the chat had I been there & have now forgotten ... so they can't have been that profound!
One thing that did strike me was the discussion about how people decide which, if any, aspects of a community to participate in - given several different vistas to what's essentially the same group.
I think that the point that Moodle could show what was in Ning (or was it the other way round??) was useful - that's always been one of my issues ... if something has several facets, is it best to use the tool *I* like best (given the choice of Ning/FAcebook or Moodle, I'd pick Moodle); should I pick the one that has the largest audience (seems to be Facebook from the feedback we got ... but I don't really like it), or the one that seems to have the greatest flexibility (which sounded as if it was Ning ... though personally I *really* dislike it).
That then got me on to thinking about how we select platforms ... I guess we tend to pick what we know & like using ... which mayn't be the preferred option for others.
Ultimately, of course, we need true "open Social", so users can use all 3 platforms (and tweet about it as well) - each participating via the platform they personally prefer - and getting the information back from everyone else.
Hope that makes sense!
Regretting missing the original session now.