So, I’m not totally pleased with this sketch, mainly the mouth. I find it incredibly hard to include teeth without them looking terrible. The mouth needs to be a teensy bit lower as well, and his forehead should be a little bigger. If I’d shaded it, it would probably look better. Sorry, Bill!
(And sorry to those who see this post twice, as I’d accidentally pre-posted it to… January 10, 2012. Yeah.)