An article by Willam Safire in today's New York Times magazine talks about the term blog, what blogging means, etc.
Given the blogging community's propensity for self-referencing and interests in anything that has to do with blogging and what blogging is, I expect this article to be referenced ad-nauseam (and I'm doing my part, of course. Everything for the cause :-)). For the moment, I've already found it referenced in Scripting News.

The New York Times. Newsweek. Blogging is definitely mainstream.

Now, to really grow up, blogging only needs to get over its "it will kill mainstream media" phase.