Dave Winer claims he has earned over $2M from his blog, and not an ad in sight. Ever. Wow.
Dave clearly gets what the value of his blog is to his business: It proves his expertise to his market with every post.
I have talked before about how online content models are notoriously poor performers if the goal is to make money directly from the content via advertising or selling premium content. There are exceptions, sure, but on the whole, unless your blog is grabbing 2,000 sets of eyeballs a day or better (fraction of % of all blog sites on the web, by the way), advertising really isn’t going to make you rich.
But if you blog to prove your expertise, to provide value to your intended audience, to extend your brand and increase your visibility, then even a modest few hundred monthly visitors can turn into a valuable increase in your business.
Content proves expertise. Use your blog to engage your market and demonstrate what you know, and you’ll stay flush with paid work.
(NOTE: I was asked by a friend how I could afford to give away so much knowledge on my blog for free, if I hoped that people would pay me for my expertise? My answer is simple: General expertise is free. Applied expertise isn’t.)