Awesome.
I think I read that you do the line work in vector and bring it into photoshop to render. The line work looks a little thicker here than anything we see in the rendered version, but crisp (no line work) in the rendered version so I'm assuming you make the selection and expand a few pixels? On some less detailed work, I do that but as you know, selection don't always fill those little cracks as well.
Do you just use that line as a guide and free render over top on another layer? I've done both but most times, once I have the guide, I free render on another layer. I try to keep the layers down as much as possible just for my own serenity.
I've known some to turn the line work down to 10% opacity or so and free render the whole thing to give more of a loose feel to it and also, even at more of a random painterly texture feel to it as well using some various painting brushes.
Very clean.