From the official annoucement:

Atari is proud to present David Sichtermann as the winning designer of the "Do You Want to Be a Car Designer Contest?"

David and the rest of our loyal gamers will get to see the people's choice race alongside cars such as the Lamborghini, Ferrari and Aston Martin as a fully functioning 3D vehicle within Test Drive Unlimited. David will also receive a financial reward of $2,500.

Two among the finalist projects of the competition: AMD Design (left) and Canay (right)

(Source: Atari)