http://www.apple.com/safari/
The market share of Internet Explorer is way down, sapped mostly by people downloading the much better and more secure Firefox, but I can certainly see Apple grabbing a chunk of browser share (beyond the 5% simply from Mac Safari users) with this. Among other things, it's way faster than IE, and also faster than Firefox.
If you're a Windows user who doesn't need to use IE for compatibility with crufty web applications that don't work properly with standards, this is probably worth downloading and trying.