A most excellent essay on groups by the amazingly insightful Clay Shirky.
Here are two lists stolen from there.
Things you must accept about online groups:
- The social and technical are deeply entangled, you can’t partition them.
- Members are different from users. “… the group within the group that matters most.”
- Sometimes the rights of the core group trump those of individuals.
Things you really really ought to design for:
- Participants must have handles that can enable continuity, aggregate reputation, and be discarded
- You will need some scheme that recognizes members in good standing: handle, member since, introduction, karma points.
- You need barriers to participation, so the core can defend the group.
- Some protection against scale (or the tragedy of the commons)
I’d add that there needs to be a shared enterprise, often a document, around which the group revolves. But that’s probably optional.