The Pew Internet & American Life Project released a new report on blogging (PDF) yesterday, with some remarkable numbers:

By the end of 2004 blogs had established themselves as a key part of online culture. Two surveys by the Pew Internet & American Life Project in November established new contours for the blogosphere: 8 million American adults say they have created blogs; blog readership jumped 58% in 2004 and now stands at 27% of internet users; 5% of internet users say they use RSS aggregators or XML readers to get the news and other information delivered from blogs and content-rich Web sites as it is posted online; and 12% of internet users have posted comments or other material on blogs. Still, 62% of internet users do not know what a blog is.