From the BMW blog (via PSFK):

BMW is presenting its Concept BMW Application Store at the Frankfurt Motor Show (IAA). It is the world’s first carmaker to demonstrate the fundamental possibility of downloading and storing individual applications either from the car at any time on the move or from your PC at home. It means that, as with a mobile phone, the car can be adapted to the needs and interests of its occupants for the first time, thus benefiting from almost limitless personalisation.

It is the logical evolution of mobile computing (mobile meaning movement and mobile meaning communication), but don’t think the iPhone couldn’t (or shouldn’t) be part of this ecosystem.
Instead of a laptop with iTunes + iPhone, it’s car with app store + iphone.