it's not in public beta yet but starting soon.
There are multiple ways to get into the Firefall beta. The first is to sign up on http://www.firefallthegame.com and wait for an invite from Red 5 Studios directly.
they are planning to do a google-type beta where the first people in get to invite friends, and those friends get to invite more friends and so on, so as long as 1 or 2 of us are invited early we should be able to invite everyone here who wants to play
oh i forgot the best part - it's 100% FREE TO PLAY - the microtransactions will get you costumes and skins but nothing affecting gameplayOur beta invitation system and user acquisition will continue to expand through December in order to ensure a stable, consistent, and fun environment for Firefall.