blendshapes.  And there's a free plug-in he can use, which is comet's pose deformer.  It is kinda like blendshapes, you push/pull verts to fix bad deformations, but it's based on the rotation of joints. 
There's a guy on cgtalk who used a combination of blendshapes and pose deformers for all the facial expressions on his Mary character..  the plus side to using comet's plug-in is it kept the scene light, but I think he used mel scripts to convert the blendshapes he already had so they were controlled by joints for the plug-in.  In this case, mel scripts aren't needed for that.
Trying to rig with just joints and painting weights.. I tried that.  And I ended up complaining a little in the body topology thread, and people responded pretty much with the same thing Odf just said.. but without the poser bit. 

divinerain