I have a 2001 S class with the turn signals in the outside mirror. If the 2002 ML's are similar, then drivers behind you and beside you will have no trouble seeing the ML's turn signals, as the light showsup/can be seen from behind the vehicle and alongside. BTW, I am awaiting a 2002 ML500 which I ordered for my wife. She now drives a 2000 ML430.
if there was this integrated turnsignal/outside mirror, then the side marker turnsignal, that is already on the ML, would be useless. if they were planning to integrate the turn signal into the mirror, they would probably remove the side marker turnsignal.