I think its a preference...I almost bought a car in NJ with cocoa interior and black exterior. I think it has a classic look to it

 

My '01 Boxster has black interior. When looking for a 997 for my wife, she wanted black interior. The dealer has cocoa brown. She's extremely picky. It took her almost a whole day to go from accepting it to absolutely loving the color and quality of the leather. It looks more classy than black and she wouldn't trade it for anything. Another friend has an '07 997 Turbo with cocoa leather, but he's scratched it up a bit. I think it's a little more sensitive to scratches than the base black leather because it has a softer finish

I've also got an '08 Cayenne on order. We got black interior because the Pepper is for the dog and she's a black rottie, so we figure it will show less dirt and dog hair.