I created the bump map out of the diffuse texture and thats actually it. I tried to use specular maps too but they don’t really work well in Cycles. So I ended up with a really simple material setup which is just a diffuse map with a bump map applied.
I noticed this render was just featured on blendernation news. Congrats on an awesome render. This thread should be moved to the gallery, clearly.
Wow, a photo of my neighbour. Where did you take it? +1
That is astounding! Great work!
Really nice!
Is it just me, or is it lacking a bit of sss?
Subtle Greg 
I actually quite like the look of it as it is. the lack of SSS gives it a cold look that adds to the character but doesn’t detract from the realism. In fact it made me go back to my self portrait 'cause I realised i’d made it too translucent.
…looks like a truly sick bastard…can’t decide whether to run or shoot first…