But it seems that for just about every other manufacturer, unless you're buying the 2007/2008 model year, its not even an option. Ford introduced the S-Max as a brand new car in 2006, and this doesnt have it either as recently as 2006 !
One more thing, the Ford Key Free system has been an option on the Ford Focus Mk2 since launch. I dont think it would suit a MPV or heavily used/practical cars.