In reply to galpinos:
Not sure I've personally ever seen it given less than ED1. I attempted it last year and the scale of it is mind-boggling. Bad conditions and some terrible logistical choices (climbing it all in B3s and not going light enough) meant that it took us two days just to reach the top of the Noire.
The Noire's S Ridge is given TD quite unanimously, I should imagine the addition of 14 notoriously terrifying abseils, an infamously chossy traverse of Les Dames Anglaises, plus an extra 3 summits and 1400m of climbing to the summit of MB warrants an extra grade?!