This is nonsense. Do you need the courts to tell you that you shouldn't be playing Angry Birds while driving, or posting on Facebook (it's technically not texting!), or reading your email? It's common sense that if something needs your attention for more than a split second while driving, you should be pulling over. It doesn't matter whether that's a phone app, a screaming kid or a paper map.
Maybe the better solution is to reinforce how dangerous "distracted driving" is, and change the laws so anyone can get in trouble for doing it.
Then the marketing could give examples of what it means to be distracted -- fighting with kids in the back seat, texting, eating cereal, etc.
My understanding from a previously posted article (techcrunch) is this applies to interacting with the map software (input), not merely looking at it, and that state appellate decisions are influential but not binding, even on the appellate court.