I just test drove one of these.
It has an amazing feature in it called Eyesight, that uses stereo cameras to interpret the world in front of the car, allowing the car to mitigate collisions by applying brakes, warning the driver of obstacles ahead, warning of lane sway (e.g. due to tiredness) and lane departure and maintaining distance from the vehicle in front when Cruise is on (even going as far as stopping the vehicle completely when the car in front stops at the lights etc!).
Of course it isn't infallible and the driver is in charge etc, but it is a pretty amazing (and Geeky) driver aid, I thought.
Does anyone have a Subaru with it?