"Not only do the looks of the car change when damaged, an advanced physics simulation helps faithfully recreate how damage is taken and its resulting effect. By doing so, Gran Turismo 5 successfully recreates real-life added tension and challenge that comes from driving on the edge."
http://us.gran-turismo.com/us/news/d5247p4.html
http://us.gran-turismo.com/us/news/d5247p4.html