Advertising Age did something called the "power 150", where all prominent advertising and marketing related blogs from SEO tips to planning and strategy, were ranked by the numbers of readers and followers they had. It checked the StumbleUpon shares, the yahoo inlinks, the Alexa points, the Linkedin, Twitter and Facebook followers, the number of RSS subscribers, as well as the Todd points.
Todd Points (1 to 15): As the only subjective measure in the Power 150 algorithm, 1 to 15 opinion points were assigned to each blog. Todd Andrlik values frequent, relevant, creative and high-quality content as well as unique visual appearance and style. The use of audio, video and graphics is also heavily weighted in the Todd Points.
The rankings went up and down depending not only on new blogs being listed but also the removal of RSS and adding of other rankable social media points.