As stated above; black is a color that is easiest to integrate into your average household. Growing up, I always associated gloss black with something expensive or of high quality. While that is certainly not a golden rule, I don't believe I am part of the minority in that respect.
When done right, piano gloss can look fantastic and compliment many rooms well - adding a touch of 'class' or maturity. Naturally, it is an absolute pain in the rear to keep clean. Finger prints, Dust, small marks - oh my!
While I tend to favor natural wood tones; I am unashamed to admit that I enjoy piano gloss!