There was also discussion with the hope that the paint scheme will be corrected as there were a few discrepancies relative to the original ANH mask. Too Much Garlic (Carsten) had shown these before so I put them side by side to show the changes that could be made, namely Vader's left side of the mouth (slightly darker gunmetal rather than gunmetal), right tubes (off-black or black rather than gunmetal) and space between the tubes (off-black or black rather than gunmetal) and the crescent shape below the left cheek (gunmetal rather than black).
Here are on-screen examples of what I mean. In lighting that is diffuse, one can clearly see the right side of the mouth as being an off-black or darker gun-metal color. The side of the U-shaped part of the nose (rectangle) might also be the darker gunmetal color, but I don't think it is pure black as some here do.
Right tubes are black...or an off-black...and not gunmetal. That much is certain (not just based from onscreen reference but still photo reference as well).
The crescent (center of image)...distinctly not black...and it isn't a reflection either.
I know it isn't a reflection because it shows up as clearly gunmetal on the Corbis photo shoot (taken with direct flash lighting).
Here is a comparison of the underlying black paint pattern of the crescent from the Tantive IV closeup above (bottom) and the same area on the Corbis image (top). The red rectangle highlights similarities in the pattern, providing proof that the crescent is gunmetal, not black. One would not be able to see such patterns if the surface was pure black.
Hopefully these discrepancies will be addressed for the final production version.