Looks like some guy over at mtgsalvation found some code in the new duels game that hints at the cards and decks for a future expansion. Looks like new red/blue, green/white, and mono black decks are in the works.
Cool player pics at that link too! This makes sense because both Ajani and Liliana appear as your "teammates" in the Archenemy campaign...
Looking forward to an all-black, non-vampire deck.