I tried it maybe 2-3 months ago. It was OK i though, just impossible to get the facial and body shape i wanted, still.
There was something about rigging for SL, but i don't know if it works or not.
The skins were terribly lacking imo.
All in all, it's just a very, very minor part of making an avatar for SL. You would still need to create alphas and a HUD for them, split the body up into parts so you could have many different alpha options. Then we have feet- these feet were all natural. Toes splayed. So you can't wear them with any shoes aside boots and just alpha that portion out.
It could be ok to use to make mesh heads, but still, blinking eyes, expressions, would all require scripting and extra modeling work.