The more I think about it the more I'm convinced its all about lighting. Unfortunately I had to pop into photoshop to brighten up the image but if poser could use photoshop plugin filters then I think we could start to see some pretty realistic images straight out of the box.

Here's one I posted today for the Classic Pinups contest.

The models certainly have enough detail these days (this one is Victoria 3 by Daz) so the limitation must be in the lighting.