Intriguing meditation by Clay Shirky on the difference between communities and audiences. Excerpt:
“As group size grows past any individual’s ability to maintain connections to all members of a group, the density shrinks, and as the group grows very large (>10,000) the number of actual connections drops to less than 1% of the potential connections, even if each member of the group knows dozens of other members. Thus growth in size is enough to alter the fabric of connection that makes a community work. (Anyone who has seen the userbase of a discussion group or mailing list grow quickly is familiar with this phenomenon.)
An audience, by contrast, has a very sparse set of connections and no mutuality between members. Thus an audience has no coordination costs associated with growth, because each new member of an audience creates only one new connection. This single connection is not even a mutual one — you need to know Yahoo’s address to join the Yahoo audience, but neither Yahoo nor any of its other users need to know anything about you. The disconnected quality of an audience that makes it possible for them to grow much (much) larger than a connected community can, because an audience can always exist at the minimum number of required connection (N connections for N users). ”
