If you want to follow the growth of blogging, look here. [via BusLib]
In short the post says "As of July 2006, about 175,000 new weblogs were created each day, which means that on average, there are more than 2 blogs created each second of each day. "
If you check the summary at the bottom, you'll find more statistics like this:
Technorati is now tracking over 50
The Blogosphere is over 100 times bigger than it was just 3
Today, the blogosphere is doubling in size every 200 days, or
about once every 6 and a half months.
From January 2004 until July 2006, the
number of blogs that Technorati tracks has continued to double every 5-7 months.