I believe they said cards will always stay the same between formats, and if I'm misremembering it's still all but Guaranteed to work that way. Blizzard has stated time and time again that they don't want to confuse players coming back to their old decks like Patron Warrior or Miracle Rogue just to find cards don't work like they used to, which is why they go above and beyond to preserve the spirit of every card.
Which means wild is going to be just that, wild as fuck. Bleck, never want to step into that ladder.