We use a paint finish which is specifically for black and dark cars. This product consists of a zirconium dioxide pigment, a very mild clear coat softener, and a hard plastic based paint sealant, much like the fixative in black polymer photocopier powder, except this stuff comes in a black cream. Only about 30 or so drops is sufficient for the whole car. The paint finish is applied drop by drop and buffed in with an ultra soft buffing pad at moderate speed. The softener only works on about the top 5% layer of the clear coat laquer, and as the buff works over it, the pigment is rubbed into any spiderweb scartches that may be present, with the assistance of the softening agent. The sealant also combines with the very top layer of the clear coat laquer, to provide a much harder surface which is more scratch resistant than before. I must say that a car prepared in such a way can still be scratched; it is just noticeably more scratch resistant, and the surface will retain it's sheen much longer, because it is more resistant to paint oxidation, as well as giving the underlying paint a pair of 'sunglasses', to resist ultraviolet attack from the sun, due to the black zirconium dioxide scratch filler. This is the exact same product applied to black Ferraris before delivery to the customer.
I will find some more details on this stuff if anyone is interested, and maybe how to obtain it.
I don't particularly like black cars, because spiderwebbing is more obvious, they are 4 degrees C hotter in summer, therefore aircon is more often required, which consumes about 4kW to run and as a result, consumes more fuel. Black cars are also harder to see at night, especially if they are not polished.