Is that camera thats part of the rear view mirror strictly for highbeam assist, or does it also work for speed limits. I've seen the Euro setup can read the speed limit signs and alert you.

To have speed limit you need the lane departure system, the camera in the rearview mirror only see's black & white, whereas the lane departure cameras see red also.

BMW cameras
 

I've asked this before, cant remember where...
If I could tap into the factory cameras ( already five, I would add two more to show the side along the doors ) then I can plumb them into a analogue to IP encoder, then store it all on a solid state HD NAS. Anyone have any info on the factory cameras? I wonder if they are analogue or digital. Does the factory screen take an analogue input - like an external DVD? If so then its likely that the cameras will input to the screen in analogue.