Also just think; how long did it take for the first iphone jailbreaks to come out, cydia for your car. Alternately replaceable ROM's for your car a la android. Where there is a closed eco system there are 100 people just staring at their computers until they figure out how to break it wide open.
If the separation between the UI and the backend electronics (the stuff that would be critical to safety) was strong enough, Tesla could even embrace a hackable UI portion of their system.
It would be up to you if the Bluetooth phone worked, or if the climate controls worked, or if any other feature worked on the main display. (I assume the cluster display would be controlled by a different virtualized process.)
Of course Tesla would still supply a standard UI that the vast majority of people would use, but it could be forked on Github if you preferred. (I assume that third-party apps would be separated.)
For all the 'speculation' about Apple merging with Tesla, acquiring a significant portion of Blackberry/QNX would be a better choice. Detroit could end up buying their interactivity from a subsidiary of Tesla.
