Geometry shell is a technology that makes a second copy of a model (e.g. a Genesis or V4 character) which surrounds the original, and at the same time the original is scaled down slightly, so it becomes like a second skin, but so much more versatile. It has its own texture surfaces, so you can set these to add texture effects and blends to the original model. You could use it to make a character glow, add hair, moisture—whatever you might imagine. If you've ever seen Jepe's body jewels and tears, "body hair suit" and tattoo system, it's like that, except much easier to manage as it takes a lot less resources than simply loading another copy of your character. It's also going to be a great help with blending textures with Geografting.

You might have missed the link in my post as they are kind of hard to see here, but there is more explanation of it there:

http://www.daz3d.com/forums/viewthread/63/

Like Geografting, I'm pretty sure it's going to inspire some exciting new products.