Firefox 4 claims that its six times faster than any of its previous releases.
It has several new features like Firefox Sync, multi-touch support (Windows 7 only),
JavaScript engine resigned, hardware accelerated graphics for Windows and Mac and HTML 5 support .
To know each and every detail as to what’s new in Firefox 4 you can refer to Firefox 4 official Page
Although you can download the latest version of the RC below.
Download