Found this on /. and thought it was interesting. To me its a major fail for companies to put inner workings of a Car's PLC that control vital vehicle functions on the same network as in cab equipment. Especially since they have no real reason to talk to eachother.
Even in factories I worked at over the years I always put production critical PLC's on a separate, isolated vlan so their was no way production network could talk to the office. Just safer that way. Even more so when you are talking about a vehicle.
If you think about it, its down right scary that someone could remotely control your vehicle and over ride your commands. I could see this getting abused rather quickly.