It hasnt yet seemed to appear in the repositores, so if your like me you probably have already gone ahead and tried to install ff2. However i made a mess of doing it to finally get it to work. I found this nifty blog with a script on how to easily set it up on your ubuntu (or debian) machine.
http://everythingelse.wordpress.com/...cho-in-ubuntu/

I havnt yet done it, but the script looks sound to me.

... Now watch as they release it in the official repositories tomarrow.