Hey g3org3,
Good eye

....the reason for this is because the thick outer outline was added using a minimum pass of completely black version of the character layered under the colored version (ie....basically a reverse matte choke).
I'll be looking at different ways to simulate that outer outline on the final render....but even if I can't find a way to do it better, I don't think it's too big of an issue.
Hey Cam,
Yea they may be....I'll see how they look once I get a finished render going on...and if they become too obscure/thin in combination with motion blur I'll thicken them up a bit.
Thanks for checking them out everyone!