Disrespecting Authority

Technorati confuses the peewaddlin’ out of me.  Specifically the way they calculate ”authority.”

A blog can have over 1000 links to it but an authority of less than 500 consistently…apparently.  And that number can drop suddenly and drastically.  Why?

Here’s the official answer:

Technorati calculates authority by looking at all links from unique blogs from the past 6 months. That means your rank will change daily based upon your blog’s activity from 180 days ago up to today. As older links fall off your count and new links are added, your link count may increase, decrease, or stay the same.

So, if you were needing to find the most influential blogs – blogs with the most unique readers every day, the biggest actual audience – authority seems like a poor metric to go by.  What’s the best one?