Just had a look at the logs for Portal Forums this month. The newly released Internet Explorer 7 preview of beta 2, has had a storming month.

Internet Explorer 7.0

MSIE 7.0 10846 hits which is 7% of total traffic.
Firefox 1.5 7805 hits which is 5% of total traffic.

The preview of beta 2 has surpassed Firefox! It's not just the Portal Forums site, all the sites are showing a similar story.