[quote name='ssjmichael']It's because it's the 5th Driver game. They also showed DRV05 in the debut trailer:
edit: Actually I think this might be the 6th Driver game[/QUOTE]
No, it's the fifth. (Driver, Driver 2, Driv3r, Driver : Parallel Lines, Driver San Francisco).
That trailer is European (it starts with Pegi 13 rating). My guess is that the plates are all DRV 05 there because it is the fifth game, and because I assume they don't commonly know what SF is short for.