It's high season for community building.
People are asking "Build me a community" like they would ask "Draw me a lamb" or "Cook me a tuna casserole".

But communities are not things that you can build away from people and then give away like a mass media or a chocolate bar.

Communities are not things, they are people who have a life and are members of a lot of communities at work, at play or according to their pleasure or their passion.

Brian Oberkirch talks about it in LikeItMatters:

Serve communities, don’t build them.

Find existing groups and add value to what they are trying to do. Participate. Host, if you must, but I bet groups are already helping themselves.

We don't create communities on the Web: we welcome communities that already exist but don't have yet a place to meet on the Internet. We can give them the magic of memory and asynchronism. They do the rest.