Google has launched a new AdWords referral program for AdSense publishers where publishers can earn $20 when they refer a new advertiser to Google. While Google had a very limited referral program for AdWords last year, they launched a revamped program from within the AdSense control panel several weeks ago for a small list of select publisher countries before making it widely available to all publishers.
The full rundown and all the details can be found at JenSense.