Human Meta-rig. Where?

Hi, dumb question maybe but I couldn’t find the answer anywhere.
Where is the meta-rig and human meta-rig option in the Add Armature menu?
I’m using the newer 2.55 Beta build 32909.

Found through the coughsearchcough

http://blenderartists.org/forum/showthread.php/200371-Rigify-Auto-rigging-system-new-and-improved