How many weblogs are there?

I’ve been digging for stats on the weblog phenomenon. It’s harder than I thought. There are no directories at Blogger.com of all the Blogger sites. Even if there were, there’s no guarantee that they update regularly, or at all, or that they haven’t moved on to greener pastures elsewhere. I think trying to count blogs is like trying to take a census, with all the potential statistical irregularity that is implied.

There is, though, one good source of data for weblog activity: Weblogs.com. I decided to look at the historical record of high water marks that Dave has kept and see what it looked like.

Here’s the graph:

weblogs.com high water mark growth is linear at abt 2.8 weblogs a day

If you peeked at the alt text on the image, you got the punch line: according to the data, overall weblog update activity has been increasing since last December at a rate of about 2.8 weblogs a day. And that’s not taking into account the blogging systems that don’t ping Weblogs.com, or that require a manual update and the blog authors don’t do it.

Next question: what’s the driver? And what does this picture look like in the long term? If there’s a network effect created by content syndication and RSS, shouldn’t the curve be exponential? Or is it too early to see that yet?

I’d love to have a better dataset to try to answer those questions. If anyone has any ideas on how to get it, let me know.