Before we truly get to the essence of most issues, greater complexification is required to address many existing nuances (at least, that's what I tell myself when I get overwhelmed).
Stephen Downes started the conversation with the discussion of groups and networks
Terry Anderson and John Dron then suggested groups, networks, and collectives.
And recently Dave Snowden adds crews and teams to communities and networks. What I find encouraging (once I get past the numerous perspectives and contexts being reflected) is that we are talking about these distinctions...we are recognizing unique elements and grappling with a means to make sense of changes wrought by technology, new forms of social organization, and information growth.