Caslon, an Australian "research, analytics and strategy consultancy", has written a profile on blogging. It is comprehensive in scope, opinionated, and thoroughly enjoyable.
It does make me ask whether blogging is the modern equivalent of the CB radio craze of the late 70s, when for one brief odd moment we all imagined ourselves to be long-haul truckers. I wonder because I've learned the average lifespan of a blog is three (3) months (thanks to Andy Coates). Interesting. Even Gartner Group agrees, predicting that the number of blogs will peak in 2007.