Gaia Clary has an update of Avastar out: RC 1-1. This version has files dated 2/10/2014.
There is also a test version out: avastar-1-1-973_blender-2-65. The files in this release are dated 2/14/2014. So, the test file is a bit newer than the RC release. There is no information on what has changed.
There is also a preview video out (updated 2 weeks ago) showing the rigging of a quadruped, horse in this case. See:
Remember. In regard to Fitted Mesh the Blender Collada export for Second Life is broken. For now only the Avastar Collada export is working for Fitted Mesh. If you are rigging to only the mbones, Blender’s Collada export works.