no problem, a quick guide i can do:
firstly, its all done with the pen tool... vector paths are drawn and then either stroked (with "emulate pen pressure" ticked) to get the outlines, or filled to get the more solid bits of colour and also all the shadows and highlights...
its all about building up layers, for the shadow layers, use the same colour as the skin and set the blend mode to multiply and the opacity to around 50%, and for the highlights the same but using the screen blend mode instead.
build up the contours to add depth...
thats pretty much all there is to it technically, other than that make sure you start with a great picture and pick your lines carefully
i was originally inspired to make something like this by this wallpaper:
http://skitch.com/sootylad/ff7n/sensuallips-1680x1050
but then i came across an article in photoshop creative which talked through the process of creating one of these vector style illustrations in photoshop... as you can see the biggest difference between the inspirational "sensual lips" image and mine is that the outlines are visible and prominent but other than that its the same effect really...
if anyone else has an attempt using the guidelines i just wrote be sure to post your pics
