Finally made some progress on the facial rig experiments I was toying with back at christmas. I've attached a rough set of deformers that seem to do the job. It's made up of a series of interdependent curves with null deformers that slide at percentages along the curves giving quite a nice fleshy feel. Since it's made up of curves, to to rig a new face you can just fit the curves on, neutralise the transformations on the controls and deformers and away you go. It also doesn't need much reweighting, except around the eyes and mouth. Here's a pic of the rig itself, then the rig in use (unweighted) on the head I made there recently. Then a quick test animation, with some sloppy blinks. For the controls I've tried to keep them fairly simple, following Kyle Balda's guides for what controls would be handy for an animator. Ah, Goebelins..

I haven't done any modeling in a good ages, so with a bit of time to spare, thought I try recreate the messy, grotesque faces of the sketches, but in 3D form.

This was quite a bit of fun. The process of scribbles and the eventual results reflect how I remember faces, as caricatures or grotesques, emphasising the main features. Since there's no real aim to the scribbling, other than to draw some heads, it's brought in facial features I recognise, cobbled together from real people I've met or seen amalgamated. “Hell is other people.”
Update 2:
Finished Drawing

More scribble heads, but shaded on the DS.