Michael,

How did you resolve the black and white surface ? Will the black have dark gray wireframe ? And how about the white surface ? (white wireframe will be more less invisible).
At the export, is it the surface color that will be taked into account to define the diffuse, or the wireframe color from the style ?

For the moment, it seems that the wireframe color = surface color + a little bright boost. Is it something automated when you choose a color for a style ?
Did you made some test with only black wireframe ? As there is some kind of soft specular on the surface, even a black surface + black wireframe will still be 'readable' I guess.

Sorry for all the questions, I can't wait to play with the color feature :)