You can only get a real and right number using tools like google analytics on the very page you are developing. There are some blogs on which the majority user uses Safari, so if it works in Firefox and IE6, this blog still looses.

In case of market share, I found some different statistics.
http://marketshare.hitslink.com/browser-market-share.aspx?qprid=2
This would give IE 70% (IE 6 “only” 22% and IE 7 47%, so nothing with 50/50).

Thanks for the input, I quite like it when stats are proved wrong, but regardless – my point still stands. Of course it’s just an opinion (one of which is shared among most) but that’s a key point behind blogs.

To all, I apologise for my misconceptions, does this however change the way you feel about the current browser usage situation?

Those stats aren’t from the W3C (as you stated), but acutally just from W3Schools visitor logs. That around %40 of their users (typically developers or students) are using Firefox isn’t that unusal, but I very much disagree with your assumption that Firefox is “steaming ahead at the moment”.

Although I can’t give concrete details (hey, who can?) the general consensus is that Firefox currently has something like 10-20% market share (though this is slowly improving). Internet Explorer dominants with between 70-80% of worldwide browser usage, and you can roughly split that down the middle when it comes to IE6 and IE7 users (with IE7 slowly inching ahead as time goes by)