Apple has updated its developer guidelines to allow developers to use all colors of the iPhone 5s in product marketing. Previously developers were only officially allowed to use the black iPhone likeness for marking, though many developers ignored this rule and used the white iPhone as well, suggesting Apple rarely enforces this rule.
Now however, developers have Apple's official blessing to use whatever color iPhone 5s body they want in their app promo shots: Space Gray, White and Silver, or Gold. Something tells me Gold is going to be particularly popular. Developers can download the latest product image templates here.