comScore made a thorough analysis of the online behaviors of blog readers: "Behaviors of the Blogosphere: Understanding the Scale, Composition and Activities of Weblog Audiences"

The result, based on comScore's permission-based research panel that measures the online activity of morethan 2 million global participants, is this behavioral examination of consumers who visited the 400 top weblog properties and blog hosting services during the first three months of 2005.

Keyfindings are:

50 million U.S. Internet users visited blog sites in the first quarter of 2005. That is roughly 30% of all U.S. Internet users and 1 in 6 of the total U.S. population

Five hosting services for blogs each had more than 5 million unique visitors in that period, and four individual blogs had more than 1 million visitors each

Of 400 of the biggest blogs observed, segmented by seven (nonexclusive) categories,political blogs were the most popular, followed by "hipster" lifestyle blogs, tech blogs and blogs authored by women

Compared to the average Internet user, blog readers are significantly more likely to live in wealthier households, be younger and connect to the Web on high-speed connections

Blog readers also visit nearly twice as many web pages as the Internet average, and they are much more likely to shop online

» Behaviors of the Blogosphere (pdf)

[Micro Persuasion]

Update 11-08, Interesting articles about the analysis:
» Blog Readers Spend More Time and Money Online
» Calacanis suggests Comscore survey is dodgy: Denton, Trott money may have influenced results