The latest version, firefox 3.5 is the fastest firefox yet, it has many new features.

To install firefox 3.5,first add following two lines into /etc/apt/sources.list

sudo gedit /etc/apt/sources.list
deb jaunty main
deb-src jaunty main

Then add GPG key

sudo apt-key adv –keyserver –reckeys 247510BE

Update and install firefox 3.5

sudo apt-get update

sudo apt-get install firefox-3.5