Some essential reading for all you drupalites, because I think what Clay is saying here may be a definitive advantage for considering Drupal not as a "Web School" portal platform, but for exactly what Dries called it, "Community Plumbing for the Web" ...

Clay Shirky: Situated Software

First published March 30, 2004 on the "Networks, Economics, and Culture" mailing list.

We've been killing conversations about software with "That won't scale" for so long we've forgotten that scaling problems aren't inherently fatal. The N-squared problem is only a problem if N is large, and in social situations, N is usually not large. A reading group works better with 5 members than 15; a seminar works better with 15 than 25, much less 50, and so on.

This in turn gives software form-fit to a particular group a number of desirable characteristics -- it's cheaper and faster to build, has fewer issues of scalability, and likelier uptake by its target users...

Drupal as a 'situated software' framework

Drupal is better than perfect for deploying small-audience applications; we have the trust metric worked out by our role structure and membership schemes, but we can do what the orkut/friendsterite artificial social networks fail to do

As was pointed out to me in Usage/TS, I've been looking at Gerhard Killreiter's work on expanding the groups and permissions system for Drupal, and mostly I merely wanted to comment and encourage him to pursue this specific path, at least to the extent that I understand it.