The car enthusiast bulletin boards occasionally have interesting discussions on the Peltzman effect and on Risk Homeostasis.

On a related note, have you seen the episode of Top Gear where Jeremy Clarkson takes the new top-end Mercedes full speed into a roundabout to see if it brakes itself properly to avoid the car in front? (It did, but there was much grimacing on Clarkson's face as he kept his foot hovering above the brake pedal "just in case".)

Devices which "dumb-ify" drivers are one of my pet peeves.
But I have a tiny little car without even cupholders, so there you go.
I shall attempt to restrain myself from further ranting on this subject.