W3Schools.com put up their August and September data after a delay due to a change in the software they use. As of September, Firefox (35.4%) is now is used more than IE6 (34.9%) or IE7 (20.8%) on that site! Also, Firefox’s overall market share (a new record high) continues to increase at the expense of IE (a new record low; IE5+6+7 sum to 57.2%). IE had its high back in March 2003, with 88.0%
The IE trends in the coming months will be especially interesting to watch; pretty much regardless of the source, IE7’s market share appears to have plateaued at a level below IE6’s, most likely due to the WGA DRM which they have now removed.
Expect IE7 share to start increasing significantly again, but overall IE to continue to drop.
(image update: I added a curve showing the sum of IE+Fx; note that its remained relatively constant over its whole range since they started tracking “Mozilla” (Gecko-based browsers) in 2003 (a high of 93.6% in July and August 2005 and a low of 87.9% in July 2006), so all the data falls within 90.75 +/- 2.85. This seems to indicate that despite Opera and now Safari being freely available, no third browser has really gained any traction)