After 12 betas (13 if you used the nightly builds), Mozilla have finally signed off Firefox 4 as a Release Candidate and made it available for download. In a posting on the Mozilla blog they announced that; Mozilla Firefox 4 for Windows, Mac and Linux has exited the beta cycle and is now available as a release candidate in more than 70 languages. The millions of users testing Firefox 4 will be automatically updated to this version and will join our Mozilla QA team in validating the new features, enhanced performance and stability and HTML5 capabilities in Firefox 4. Mozilla have also encouraged testers to put the browser through its paces by visiting the Web O’ Wonder which features cutting-edge demos targeted for Firefox 4. Developers are also invited to submit their own demos to the Mozilla Developer Network Demo Studio. The Mozilla team also claimed they have fixed more than 8000 bugs since the first beta, putting into perspective the huge task undertaken, and why there were so many beta versions needed. Firefox 4, based on the Gecko 2.0 engine, brings an updated user interface, new ways to organize tabs, a revamped add-on manager, support for HTML5 video standards, multitouch support on Windows 7 and a range of performance and security enhancements. You can grab Firefox 4 here.