It would be the same manufacturing process for the "core" Wii unit (PAL or NTSC). Australia uses PAL - but the unit supports both systems. Im sure its just software that controls the language/BIOS (and maybe even this is the same everywhere - just a country code). The hard bits to make are the controllers & main unit - power supplies are easy to make/get, and they could easily change the orders if they wanted to redistribute units elsewhere. It may well be a "strategic" redeployment of units to Europe - customers go to a store to buy a PS3, see Wii's in stock (less than half price, with a game) and get that instead. Something like that anyway. I can't comment for Europe, but I still haven't seen *any* Wii's in stock here in Australia - still at instant sell-out stage.
Gesta Non Verba
Nocturnal is helping companies get cheaper game ratings in Australia:
Wii code: 2263 4706 2910 1099