I don't know what a monopoly is until someone tells me - Steve Ballmer
Windows, Linux and Mac downloads are available from this link here at the Mozilla releases page.
For you British-English speaking users, here's a direct link to the Windows build, Linux build, and Mac build.
Microsoft's pipped the Mozilla Firefox team to the post by a matter of days, releasing Internet Explorer 7 last week.
It's expected that the Firefox auto update feature should kick in tomorrow and alert users of the new version. ยต
See also
Firefox 2 out tomorrow
IE 7 reviews mixed: good, not great
Vista and Firefox go RC2
Symantec lashes out at Firefox