As usual, a great post that really resonates with my own experience (and thinking).

I would add that we sometimes get all tripped up over the use of "community" in community-of-practice, in the context that you use it here. And I am familiar with Wenger's work and his (and others') distinctions between communities and networks of practice. I really do believe you are spot-on about CoPs being a key third piece - but I think that we might want to focus more on the "practice" part as the glue. Whether or not it is a community (however we define it) becomes slightly less important that there being some kind of authentic, open, trusting, I-know-you- well set of networked relationships based on a common practice.

I, for example, am diving a good deal into the MOOC world. (Who isn't, right?). I have a set of very strong relationships with people of similar backgrounds (higher ed, pedagogy geeks, ed tech enthusiasts) and we are continually solving real problems and testing out ideas and sharing results. Are we a "community?" Maybe. Maybe not. In the end, I don't care a whole lot. But I just know that ARE something that lies between work teams and social networks.

Either way. Thanks for the post and the opportunity to think out loud.