> I'd argue that safety critical vehicle software should not be downloadable. If a fix is needed, the vehicle has to go back to the dealer for a new memory module. This would discourage "shit early, shit often" software development, and encourage manufacturers to keep the safety critical systems, like ABS, totally disconnected from the entertainment system.

Better yet, the software should be uploaded to an intermediate agency, that is responsible for the testing of cars (could be part of the US Department of Transportation for example). Only this agency can (after sufficient testing) upload the software to the actual cars.