The blogosphere's more outgoing and informal social nature provides an opportunity to exploit more socially oriented features, such as credibility and popularity, for searching, recommendation, and other tasks. In this article, the authors present evidence that blog popularity in particular has been underexploited by current search engines, including specialized ones, and that a low correlation exists between such popularity and a blog's perceived importance in a Web graph, as measured by PageRank. The authors suggest that incorporating popularity into search engine ranking could result in significant gains in retrieval effectiveness and thus user satisfaction.