ENN reports on a recent survey that details how Americans are using the Internet. 53 million of them have published a journal, written in response to others, or have shared files on the web. That breaks down to approximately 21% who admit to have posted photos on web site ("could be taken on a holiday?"), 17% who have published material on their web site, and only 13% who own their own web site. I guess owning a web site doesn't mean that you'll actually write anything on it - which is true if you look at the attrition rate of journals and blogs.
Regarding the blogging phenomenon, it's not as prevalent as the causal reader might suspect - or else this survey didn't get a good market sample. Between 2-7% (which is a big marginal difference) of American users have created blogs, and roughly 11% read online journals. Interestingly, online content is evenly distributed between men and women, which is a promising sign.
As usual, for someone who uses the Internet a lot it appears as if everyone is either reading a blog or is writing one. In fact, as a percentage of the entire population, it still remains the domain of the geeks and the computer literate.