Thanks all for the info, but being a crazy bunch, you've cleared-up one curiosity and created another :-D

I thought the whole idea of Genesis is that they don't need to change the base mesh itself.  If Genesis 2 has a different poly-count to Genesis 1, then surely any morphs aren't compatible between them.  And like RorrKonn, I'm curious what the G2 stands for on the Poser figures.  To hazard a guess I'd the say the "G" stands for "Generation", but those figures aren't the second generation of Poser figures so Generation 2 wouldn't make sense.