Till now firefox has released till 12 beta versions for Firefox 4, finally Mozilla Firefox is current has released version Release Candidate for Firefox 4 and has can be downloaded. Release Candidate is final version of an application after beta that published by the developers to release Final version.
Firefox 4 walks at Gecko 2.0 web’s platform. With Firefox 4.0 RC browsing will quicker, stable and are considered more safe to be used when doing browsing and opened website. Firefox 4.0 RC also has heavily supporting and can use add-ons available of formal site firefox. With menu display that then will also facilitate us in managing special characteristic of a products and addons
Differ with Firefox 4 the Beta when installed will separated from firefox 3 and independent, so whenever you install Firefox 4.0 RC then Firefox is old you will be automatically updated to Firefox 4.0 RC’s version that new
Update – Download : Firefox 5.0 Final
firefox 4 release