Here is a transcription to Chris Locke's piece on NPR Marketplace talking about the blog phenomenon.
Garbage to one person is of high value to another, and the way the Internet works is that people group together around things that interest them. So the audience isn’t the mass audience, it’s little tiny micro audiences that aggregate around things people are saying that resonate with their own concerns. There has been an enormous amount of stuff written and said about the phenomenon of weblogging, which two years ago didn’t exist, and today there are something on the order of two million of these things in existence. It’s been a hockey stick spike.