Well I have heard that WII remote accelerometer is very good, but how its performs at track is different story. It needs to bee tested. There are ways to reduce this "position error as the square of time" dilemma at race track. Simple way it's users sync as new lap starts users taps screen, preses button or plays a sound. Little advance method would bee use WII IR leds, but if WII IR can't receive its more tricky. As in map or navigation mode it should bee hard to correct your position every now and then. When we have tested results how long accelerometer error stays in reasonable rates. We can time gps or users syncs accordingly.
Does somebody actually know more about WII remote. How sensitive it is, can it be programmed in any way, Whats is power consumption in active use, Does it draw more or less power than gps receiver ?