1. Blazing fast Firefox 4 beta 7 impresses By Ars Technica
… Ubuntu, Fedora, OpenSuse, or any other Linux distribution. This howto explains how to install Firefox 4 (Beta 9) on Linux distros, without replacing your current Firefox installation. Firefox 4 Beta 8 was released on December 21, 2010. Firefox 4 Beta 9 has been released on January 14, 2010. More information: releases wiki.
3. How To Install Firefox 4 In Ubuntu [Maverick 10.10 & Lucid 10.04]
Firefox 4, currently in beta, is one of the latest versions of the Mozilla Firefox browsers and has some of the all time best features of the Mozilla Firefox browser. We had reviewed Firefox 4.0 Beta for Linux sometime back and found that it is around 30% faster than Firefox 3.6.6 (the current stable release). In this article we will tell you how to install Firefox 4 Browser in Ubuntu Linux using the Ubuntu Mozilla PPA (repository).
This beta version of Firefox 4 browser from the Ubuntu Mozilla PPA is compatible with the following versions of Ubuntu linux.