Here's the result of some experiments with bagginsbill's VSS PR2 skin shader. I've yet to come to grips with PR3, which supposedly is much better.

Anyway, I modified Bill's supplied "Spots" node for pigment variation a little bit and added a second one to imitate that typical faint bluish network of veins below the skin.

I think this together with a lo-res color map could already produce some pretty awesome skin.

-- I'm not mad at you, just Westphalian.