I am seriously thinking of seeing if I can tie a USB or iPad connector into my factory car stereo. If so, I have a dash storage tray that is about perfect for the iPad. I may even be able to do a flip up holder to use it as a GPS.
I don't think so, for one reason, the main demographic for those back seat entertainment systems are people with small children. Sorry but I'm not giving my 3 year old an ipad that costs 500+ dollars to hold onto in the back of the car. Not that I have a 3 year old, my kids are grown. But I wouldn't give it to my hypothetical 3 year old grandchild either.