Zoroark is unlikely at this point.
Remember what Sakurai said in how Pokémon are chosen?
The process starts with what's the "hot" Pokémon. Which Pokémon are appearing in the movies, the anime, promotional material, etc.
Zoroark's movie is back in 2010/2011.
Since then, we've had two movies (technically 3 with the two versions of Victini's movie), and an upcoming movie. Said upcoming movie stars Mewtwo and the new Mewtwo form, as well as Genesect.
Now, that's not to say Zoroark has nothing; Zoroark recently had an episode in the anime.
However, that's pretty much it; Zoroark isn't promoted much, and hasn't been a big promoted Pokémon for B/W since the very beginning of the generation. Prime focus for promotion was given to the Tao Dragons and the starters, with Victini squeezing in every now and then.
Even for B/W2, when Zoroark was seemingly coming back, previous Gen mascot Lucario stole Zoroark's thunder, being marketed alongside it to start with, then by itself shortly after. Hell, Zoroark replaced Lucario as a mascot of the Pokémon talk show in Japan when it changed from Pokémon Sunday to Pokémon Smash!, then after a bit, Lucario re-replaced Zoroark. To this day, Lucario appears every Sunday on the talk show.
And like Zoroark, Lucario was also in the anime again, when Cameron's Riolu evolved during the Unova cup against Ash and wiped out his remaining Pokémon, eliminating Ash from the cup.
In summation, if Lucario is gone, Zoroark will not take his place.
Outside of Mewtwo, who was in Melee and planned for Brawl, the main Pokémon to look to is Genesect.
Not saying this as an anti-Zoroark, since I have no problem with Zoroark being in the game. However, facts need to be faced; Zoroark is a victim of bad timing.