My copy finally turned up this afternoon.
The handling. Body movement is good, grip levels seem reasonable.
The course maker.
The flickery shadows on the car.
The flickery and jaggedy shadows cast by the car.
The jaggedy outline of the car if there is smoke/spray/dust behind.
The gale-force rain spray at Monza, despite an absence of tree movement, or even sideways rain (clearly just a way to stop it lingering and making the jaggedy outline of cars look bad).
The absence of Seattle.
The absence of any sign of headlights in the interior mirror on a night track.