Steven Den Beste of USS Clueless has a recent entry about how various blogging cells are formed, complete with illustrations which instantly reminded me of the sprawling, Spirograph-like interactive diagram on Casey Marshall's "A Picture of Weblogs" site.

Den Beste identifies several cells which have sprung up over time on the Web: the warbloggers, the E/N crowd ("everything and nothing", the day-in-the-life bloggers), the A-list, (the original bloggers, often obsessed with the Web and its possibilities), the Catacomb (religion and its influence on politics (and vice versa) the Gay Underground, and other blogging cliques.

Pretty much any collective interest which used to spawn a news group has probably spawned a blog cluster now. For example, I suspect that there's a Mac-lovers cluster out there, and probably one for dog-lovers, and I have no doubt at all there's a Jewish cluster, and bird-watcher clusters, and weaving clusters, and likely dozens or hundreds more. Some clusters will form simply because they're circles of friends, not because they necessarily have a subject in common. By the nature of this medium, there's a sort of blog gravitation that tends to make clusters form.

Perversely, this has two effects. If you find a member of such a cluster, it makes it easier to find others in it. But it also makes finding the cluster difficult in the first place because there's less cross-cluster linking going on. It never occurred to me until a couple of days ago that anything like The Catacomb even existed.