“My anxiety about the blog world is not that it will put us out of business but that it contributes to an erosion of middle ground, that it accelerates a general polarization of the nation into people, right and left, who are ardently convinced and not very interested in exposing themselves to facts or ideas that contradict their prejudices.” – Bill Keller, executive editor of the New York Times, in an email to Jeff Jarvis, who dissents. The point, surely, is that the blog world can go either way. It’s not a utopia. It’s subject to the same polarizing forces that beset a deeply divided polity. Jeff’s blog is one that manages to build some kind of dialogue between the two sides, in his own internal discourse. But that’s rare, isn’t it? And isn’t it rarer now than it was a year ago?