You can now transfer your objects to your game system from Second life and Opensim.
A nice video from John Lester explained it to me today and I just tried it out.

Here is the link to John Lesters Youtube video.
https://www.youtube.com/watch?v=lTlnKOYGFrk
 

singularity transfer
My objects on Opensim conference grid.
blendertransfer
And in my Blender.