http://www.bopnews.com/archives/000120.html
"In the blogspace, both Atrios and Instapundit help direct the general conversation. Aside from the influential reach of their audience, both Instapundit and Atrios are read by thousands of small bloggers, who often follow the linked stories and add their own commentary. A link from either Atrios or Instapundit will result in thousands of visitors to a site. In order to garner a link, bloggers will tailor their writing to what Atrios or Instapundit wants to have featured. The influence of these mega-bloggers thus radiates outward; what they talk about is what the blogs are talking about.