I think it depends on the company. Incidentally, have you seen the inside of a MacBook Pro? It is awesome. Black PCB with orange/yellow highlights. Even the grommets for the screws and the HDD bracket are the same orange/yellow color. They really go out of their way to make the inside look as nice as the outside. Very few companies do that.

It was only relatively recently that modern PC motherboard manufacturers started doing the same, but only because the market was driven by the hobbyist/modding community (who else!)