Today I chucked the instructional DVD I've been working with and instead just referred to the skull models I have. The DVD has it's merits (led by a guy who does a lot of CGI) in that it was good for the first part of the sculpt, figuring out the general planes and proportions. But now that I'm getting down to the nitty gritty it's much better to be working with an actual model. I mostly reworked and refined the cranium today refining the generalized CGI-like planes for a more precise realism. I also retooled all of the facial features. It's a bit of a challenge as I have two skull models that are quite different (one male, one female, and I think some ethnic differences as well), plus I'm working off of my own skull's dimensions. So this is more "best guess" than an exact replica of either of the models I have.

A side view -- wish I'd taken some profile pics with the previous incarnations. Haven't touched the cervical vertebrae in a few days, so it's still in "blocked in" phase here: