I dont think its an official recall,as the pana guy said its so far been a very small percentage of camera,s effected.. but they seem to be acknowledging that the plastic wheel/gear is a bit sub standard and will replace with the metal ones,for free, they have been using since August 08.. not sure of that date 100%.
My guess is ofcourse it depends on the amount of use the camera gets and if the filter wheel is snapped around or not.. ?? but seems a good idea to change it anyway if your camera is going in for a service..