Dane Carlson's Business Opportunities Weblog has a tool on it which allows you to submit a URL for a blog, and to determine the value of the blog, based on the same link to dollars ratio as the deal between AOL and Weblogs Inc.
Using this measure, Luminosis is worth around $560.
However, Designated Import is worth $2,260, and fandrogyny is worth nearly $12,000. John Scalzi's Whatever is worth just shy of $664,000. Unhappily, Karl Schroeder and Mutatron are worth zero. I didn't check any others.
I don't think I take these valuation numbers very seriously, but still and all, these are good for entertainment value. Were I a self-promoting kind of guy, it would now be possible for me to say, truthfully, that my blog, Luminosis, had a higher valuation, according to an independent source, than the blog of one of the finest science fiction writers of this decade.