You might think the world's motoring press would be used to the idea of celebrity launching cars. It happens all the time, and there's nothing like familiarity to breed cynicism.

But the busiest press conference so far is the Audi event. Not, i suspect, because of the A1, either. It's busy because Justin Timberlake is about do us a song.

Geneva motor show: Audi A1 launched

He probably won't be singing about the A1, but it's paid off for Audi as there almost as many people here as there are left on the show floor. Expensive, too, but the car will be everywhere, including some magazines and on some TV programmes that wouldn't normally bother with cars. And yes, I'm writing about it too, thereby proving (or maybe disproving) the point I started out with.

And the car? I can't tell you anything about it yet because of the wall of people in between me and it, who are here to see Justin. Perhaps this stunt isn't working too well after all...