As mentioned in my last post, I've been reading about early online communities, specifically "The Well". In these early days, you didn't connect to "The Internet", but you used your modem to dial into a specific computer. When you got on The Well, you were on The Well. There were different topics to discuss, etc., but it was just one "place", all designed and run by the same people.
My suspicion is that the narrowness of the community helped to give identity and cohesion to the members of The Well. The online landscape of today is strikingly different, and there are a few ways that I think make community-building more difficult.
First, community cohesion means choosing a community that is "yours", and with so many communities, I think it's easy to try to be a part of all of them, without really joining any of them. I have edited Wikipedia articles and answered questions on Quora and written blog posts, and taken Udacity courses, etc., without becoming involved in any of the communities.
Second, our experience of communities is in many cases individualized. Our Facebook news feed isn't the same as anyone else's, nor is our Twitter feed, Quora homepage, etc. Part of community is shared experience, and our filtered versions of the world mean that we experience online community differently.
I'm not sure whether this is good or bad. I guess, as I read these memoirs of the early days of Internet life, it makes me wish that that same sense of deep belonging still existed, and has led me to think about what has changed.