I also see white and gold. However, this could go back to Kant's idea of a priori. We perceive things through our sense organs, but we will never know things in and of themselves, because everything is a function of our limited senses.
While these perceptual concepts may vary among individuals, Godel was pointing out that within any system, there is always one fundamental flaw which it cannot prove; one fundamental blind spot.
So, using this dress as an example, and maybe stretching his theory a little, the blind spot for humans in general could be our varying degrees acuity in our sense organs.
This last paragraph is more of my opinion. What do you think?