Mozilla fans rejoice! The Firefox 4.0 beta for Mac, Linux, and Windows is now floating around online and for the first time brings 64 bit support for Mac OS X. A word to the wise though, this beta is definitely not for the casual user as it comes with a number of stability warnings and will probably be quite buggy until it reaches public beta stage. However, for those amongst us who revel in coding, and who want to check out (and help with debugging)  the latest and greatest from the open source Mozilla community, this release is your chance to lend a hand in the development of one of the most anticipated browser releases in recent times.

This latest release of this giant among browsers promises a cleaner UI, Chrome style tabs (Windows version), and some fairly impressive SunSpider Javascript test. For a preview, you can swing by the Mozilla nightly builds page and grab one of the “.dmg” files shown in the image above. The Firefox application itself is currently codenamed “Minefield” (seems rather appropriate).