Mozilla has set the public release date to March 22 for Firefox 4, its popular open-source web browser, should no critical vulnerabilities or bugs in the software arise during their final testing.

Last week, the company made the Release Candidate build available, stating that it was likely to be the final test version. Mozilla is quite eager to get its browser to market after rival Microsoft released Internet Explorer 9, the newest version of the browser that has been credited with starting what we now know as the “Browser Wars”.

In February 2011, Internet Explorer was the most popular browser with 44% market share, followed by Firefox with 29%. In third place was Google Chrome with 14% usage. IE9 offers a new interface which maximizes vertical space for websites, much improved performance and Windows 7 application shortcuts.

Firefox 4 has an updated user interface, some new features such as grouping tabs together and is allegedly six times faster than the previous version. The new browser has marked a major change in performance in comparison to former versions 3.6 and 3.5 and has made significant improvements in supporting HTML5.

Since Firefox 4.0 Beta 5, hardware acceleration is enabled by default on Windows Vista and Windows 7 machines using Direct2D. Using hardware acceleration allows the browser to tap into the computer’s graphics processing unit, lifting the burden from the CPU. This allows pages to be rendered much faster.

Unlike Internet Explorer 9, Firefox will ship across multiple platforms, including Windows XP, going up against Microsoft and Google’s Chrome browser.

Download link for IE9: Microsoft Internet Explorer website

Download link for Firefox 4 RC: Mozilla Firefox 4.0 (rc1) download page