Bloggers seem to spend most of their time discussion other blogs. It is therefore very interesting to see what "influential" bloggers think are "influential" blogs. The Online Journalism Review has an article on just this subject.
"This past year has seen the world of Weblogs, aka the blogosphere, grow in power and stature, if not to the general public, then to the other media. On Iraq. On Trent Lott. On The New York Times scandals. So we've created a graphical depiction of what I believe are the most influential blogs, pushing the direction of media coverage and perhaps even public policy. These blogs are either focused on the business of media, current events, politics or some combination of the three. They cover the media or have been covered by the media."
For a really good analysis of how blogs influence each other, be sure to check out the "mouth" charts at the bottom of the article. Each mouth takes you to a blog showing it's own influential mouths --can't explain it, you just have to go there and look.