[citation][nom]ukgooey[/nom]Years ago, I went through the whole Car PC phase and it was awesome. 300Gb HD (which was massive then) for movies, music and TV plus Sat Nav and phone control through a 7" touchscreen moulded into the dash. Specifically, the connection to the OBDII allowed me a certain amount diagnostic capability (and some really cool graphs/charts etc.). Wifi and bluetooth also.This was of course entirely customisable, down to the skin and music visualisation and used whichever conventional ports I wanted to use. And this was 5 or 6 years ago.
I almost always use Linux and I'm no dummy. Don't knock it 'til you've tried it. Apple's business model sucks hard.[/citation]
OBDII port stuff is extremely simple. Sure you get access to engine data, but that's about it. You may have had, for example, NAV done on your car PC, but this system is using Apple devices as a front end to control the vehicle's systems. This is WAAAY beyond using a simple OBDII connector.
This Mercedes uses multiple networks (CAN, LIN, MOST as an example) and different computers in the vehicle are connected through different networks depending on their requirements. For example, engine, transmission and ABS/stability control would be on their own dedicated high-speed CAN network to allow for extremely fast information transfer between them, something needed when the vehicle needs to make a lightning fast decision.
Some of these networks use twisted pair wiring, others use fiber-optic. Some modules will actually have both types of connections (like gateway modules transferring information from various systems - like getting radio/stereo information from the multimedia network to display on a different bus connected to your instrument cluster).
Brabus, with their close ties to Mercedes, would have access to the various protocols used in this car, which would allow them to develop specific interfaces to allow external devices access to control vehicle systems. It is very likely they have direct access to the vehicles networks and didn't even bother to use the OBDII port.
This whole undertaking wasn't done by a couple people "fooling around" with integration. They would be highly skilled engineers at the same level as those that develop consumer products that we all buy and love.
These same people with this amount of incredible skill chose to integrate Apple products into this vehicle. They are very likely far more intelligent than any people posting in this thread. Which is why I laugh at the people saying it's a stupid, crappy system.
BTW, I've tried Linux. I don't use it because it can't run any of the software I need. All of my development tools, compilers, engineering software and the like run on Windows. Period.