I think there's some kind of consensus that a balanced combination of those major elements moves us in the right direction toward realistic characters - that no one thing takes priority.

I agree with most of the comments in the responses so far, with a couple of differences.

While I agree that in terms of meshes,  textures and morphing functionality it is entirely possible to create the shapes and base diffuse colouration for a good level of realism (for still images at least), I think by far the greatest challenge remains the lighting, shaders and rendering options of the apps in which we're rendering.
This is certainly true of Poser 8 IMHO - lacking a convincing SSS or translucency shader,  transparency still seems an issue with IDL, and although I can't quite put my finger on the problem I find it very tricky to balance out diffuse and specular lighting/shader effects (particularly maintaining shadows - but that's a whole side issue). There are aspects of IDL that also present difficulties. Maybe there are problems with how all the various systems implemented in Poser interact with each other. Not intending to bash Poser though - it remains a very powerful and capable app for the price.

I don't actually like trying to assign a percentage value to any aspect of this 3d process, but I feel that even a fabulous mesh/morph/displacement/bump combination potentially only gets you 50% of the way toward (photo) realism. The lighting, shaders and render options are hugely important.
Oh, and not forgetting a touch of posing and expressions in those faces.

bb has had a massively positive influence in terms of helping us to understand and use the material room and lighting in Poser - I think it shows in many more renders that I see in the galleries. I'd like to see more development on enhancing and fine tuning these systems in Poser itself.

 

PoserPro2014(Sr4), Win7 x64, display units set to inches.

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