Nancy, thank you for your most thoughtful comment.
Yes, this makes a lot of sense, and thank you for sharing — your definitions are nearly quotable in themselves, especially as they so clearly demonstrate a distinction between them. I suppose my challenge in this area is that I do not have such a strong distinction between them.
I do not have the strong sense of community as you described it, and from a network perspective, often see it more as an extended community. Continuing this thinking, I do not have those strong and distinct boundaries that you listed. In many ways, my experience is often more focused around specific initiatives and experiences, and thus the community tends to expand and retract along the way. As a number of the people I know tend to be involved in more than one at a time, it feels more like an extended and distributed community of practice.
I also find that when I am busy with work and academic commitments, I tend to withdraw from my communities, as there is only so much time and I have been known to over commit.
I find this very useful, as I have not consciously processed all this in a similar manner before. This gives me food for thought today, when all I thought I would get is food for food’s sake!