Firefox 3 is released on 17/06/2008.
All Firefox users made a Guinness record by downloading over 1.7 million copies on a single day.
Mozilla foundation gave a certificate for the downloading users.
The above is mine.
Get your own copy of Firefox -3 at http://www.spreadfirefox.com
View the Download statistics here.
It shows 21,440,198
and it grows well.
See the Firefox 3 features here.