Wait a minite, Didnt PD Make Really High quality 3d models for GT4 on the computer, Then Seriously downgraded them to put into GT4 so it could keep a steady frame rate? If so,
The Standard Cars we have been seeing are the original High Quality models, I'm guessing kazunori knew he was going to use them for GT5 "Smoothe mooth"
Actually In some parts of GT4 you can see the very high quality models of the cars(Just in ps2 engine quality)
Like coasta di amfali, Take any car on to it and the Reflections Are that of PS3 reflections, Tail lights and headlights reflect in real time, Chrome Looks like Chrome, Textures on the car's are highly detailed, And the lighting look's almost like prolouge,
So standard car's are the High quality PreGT4 models, But now, They are brought up to PS3 Level, Increased Polys, Better textures, GT5 lighting engine, and reflections,
For Standard Cars they look damn good.