X-Men: Days of Future Past director Bryan Singer is back on Twitter today, revealing a production office wall of actors' headshots. As you can see below, there's quite a few familiar faces, a few surprises and what appears to be six empty slots. Of those faces, the final three have not yet been announced and the first appears to be that of Daniel Cudmore, who played Colossus in X2 and X-Men: The Last Stand. We'll have updates on the other two faces as soon as they can be confirmed.
UPDATE: We've now confirmed that the third new face belongs to Boo Boo Stewart, best known for his role in The Twilight Saga (alongside Cudmore).
UPDATE #2: We've now also confirmed that the other headshot belongs to Fan Bingbing, a Chinese actress best known for films like Battle of the Warriors and Double Xposure. She will be playing the teleporting mutant, Blink.