I honestly think all this speculation on what an Apple car will look like is pointless.
I think it is more likely that apple will be focusing on the computers inside cars to have an apple (OS) feel and quality.
Consider the following; all modern cars have really large displays and fullout, onboard computers, however there isn’t mush standard when it comes to size, interface, software and how it integrates. Every car company kind of does it their own way and though they look really cool, I feel consumers are impartial to them. People care more about the quality of their ipad displays and than the screens in their cars, in fact most people probably dont even care about the screen in their car or the software involved when making car decisions. Its kind of a ‘meh thats cool to have a digital display, but it is a nominal perk and I wouldn’t care if was there or not,’ after all, everyone at some-point was perfectly comfortable with analog feature in cars. Personally, when I see glimpses of UI in ford or BMW it looks totally alien, confusing, and glitzy-glammy. What?! now i have to learn how to use this weird OS from fast and furious that I have never even used before? Its like trying to use an old gaming console with some weird navigation…its not windows and its not apple, what is going on, how do I get it to do what I want? I give up.
Apple will probably try to capitalize on that, by developing --you already know-- , apps, software, UI, iconography, and most of all ties your car into your, phone, pad, computer family of electronics. People will say ‘wow, that onboard that I once overlooked when considering purchasing cars is now an apple and really understands me and my driving needs’. Car makers will say ‘we need to design to incorporate apple OS to sell more’.
I would say this is an obvious if not overdue step for apple and I hope there is success in the end.