I'm a software engineer, but don't have any experience dealing with low-level linux based systems. I would love to be able to either install custom, modified linux operating systems in the car or just be able to alter parts of the system to enable hidden or disabled parts of the system.
For instance, every european market has the ability to buy connected services (live traffic, weather, etc), and the Japanese market even can play DVD's and watch live TV!
This may at least give us the ability to upgrade our own systems without visiting the dealer, or use other applications through our phones such as Waze.
What I think may help here is getting the update code dump. This would be solved easiest if someone knows a dealer that can get the update software on a USB stick. If someone could upload that somewhere, we could then start analyzing the update procedure and the software and hopefully fine some way to hijack onto that process.