This is a safety feature incorporated into most new Volkswagens (excluding the Lupo I think).
In the even of an accident, a driver's foot can slip off the pedals at the
point of an impact which can cause damage to the foot and ankle. To try and
prevent an injury like this VW have created a system where the ECU will
detect fast deceleration and impact. When this situation occurs it will
automatically draw the 3 pedals (I can't comment on whether this is the same for an automatic) back towards the engine by about 18cm, moving
them away from the driver's feet.
Taken from a list of cool technical features on new VW models I found while rummaging through my desk at work.