They've had in-car devices for years, in fact they made in-car phone systems before pocket-sized phones.

Whether they'd take that any further with multimedia etc features is anyone's guess, but nothing like that has been announced.

I would assume they would do "in-car" simply by providing mounting kits for existing mobile hardware, like the N810's car kit. That could become especially popular now that more of their phones are getting touchscreens.