The page is for PC members, so here's a summary of the info posted:

• better joints, and fewer JCMs needed
• 'more than double' the texture map resolution (presumably that refers to the maps to be supplied with V4)
• if I'm interpreting correctly, no more morph injections
• something called 'Morphform' dials for controlling multiple dials with one slider

That's about it so far.

Steve