While the Novus Ordo was universally (in every vernacular translation) using "for you and for all" during the Consecration, it was very likely invalid.
Now that they have reverted to "for you and for many", and since their Anaphora 1 (i.e. Canon 1) is almost verbatim the Tridentine Canon, I think that it's likely valid ... when they use that Canon. Not so sure about the other ones.
BUT, ironically, as if by design, they only reverted to the valid formula of consecration after nearly all the pre-1968 ordained priest had died or retired. So the NOM is still positively doubtful, but now it's more due to the fact that the New Rites of Ordination/Consecration are positively doubtful.
But if a validly-ordained priest offered the NOM using Anaphora I, I believe that it's most likely valid ... although I still think there's room for positive doubt (due to their having messed with the Offertory).