Lol - Sam, we'll have to agree to differ on that one! It could be that the cables concerned are not aimed at those who see audio equipment as 'jewellery', and nothing to do with how good they are or not.
The cables in my system are mainly professional types, used in recording studios/broadcast houses, and those tend to be black or grey. The 'business end' of their performance, where the quality counts, is top-notch, and revealed 'under their skin', as it were...
Nope, I don't buy into the 'sexy' thing with cables at all. The only non-black cables I've got, apart from as Barry has mentioned, a digital coax lead, is my VDH speaker cables, which are 'peach' coloured, and as they lie on the floor, are now covered in accumulated dust/dirt from over the years and look black!
Marco.