A new release is out. There are reports of some new problems for those importing rigged mesh to Second Life. Some rigged Collada model uploads are failing. The Lindens know the reports and in yesterday’s Mesh Content group it was discussed. So, a fix is already in the works.
This is the big NEW feature for this release. However, it cannot be used for anything in Second Life. The SL viewer has its own sound system. This feature is for those making animated videos and games in Blender. It is an OpenAL thing.
This is an improvement to an existing feature in Blender. The user interface has been polished and usability improved. Also Collada integration has been improved; I suppose they mean integration with the animation system. The release information links to a section on Full Collada Animation Support.