In the September 2007 survey we received responses from 135,166,473 sites. This is an increase of 7.2 million sites since last month, the largest growth in the number of sites recorded by the survey. The rate of growth, around 5.5%, is high but not exceptional by historical standards.
The high growth so far this year has been largely driven by the increasing number of online blogging and social networking communities. This month sees strong growth in the number of sites at Windows Live Spaces, MySpace, and Blogger appearing in the survey. The increased popularity of these blog hosting services continues to have a dramatic effect on the web server market shares: Apache suffered a sudden decline in share when sites at Blogger switched to Google's GFE.
Apache gains over 3 million hostnames, and around 0.9 million active sites this month. But this is not enough to prevent its market share declining closer to the 50% mark, as Microsoft also gained over 3 million hostnames (a large part of which come from MySpace and Live Spaces, both of which use its Internet Information Server).
A more detailed list of servers is given here.