
Face no doubt, abs, back and ur ass are the last places you get ripped I think 
upper abs >>>> face > lower abs >> ass ? I think ass is always last.
And i'd say that upper back comes lean much earlier than lower back/sides.
If 'face' refers to chin/jawline i'd put that quite early too, and sunken cheeks/cheekbones a bit later.
edit: there's an interview of dorian yates at a crazy low bodyfat where you can see those muscles around the side of the mouth. that might be second last before ass.