I was worried about this when I got a car with adaptive cruise control and lane-keeping assist. It's not enough automation to allow you to just do something else, but it's enough to give your brain significantly less to do. I was concerned that driving would fall under the threshold of too boring to pay attention to.
In practice, it turns out that I use the spare bandwidth to pay a bit more attention to other objects besides the car directly in front and the lanes, e.g. cars on other lanes that look like they may switch without signaling, cars further ahead whose behavior may suggest problems ten seconds from now, things like that.
It's when you get enough automation that you start feeling like you could check your emails - that's where the real danger begins.
Biting the hand that feeds IT
