After an extensive beta testing program, finally the FireFox 4 is now officially launched. Download it from below official Mozilla download section -> http://www.mozilla.com/en-US/firefox/all.html
This time, with FF 4.0, Mozilla would also explore the ongoing smart phone market by making FF 4.0 mobile edition available for Google AndRoid and Nokia 900 platform.
FireFox 4 Mobile -> http://www.mozilla.com/en-US/mobile/download/