There's a simple formula for determining whether or not the Sith will be in the new trilogy. Disney/Lucasfilm will NOT make a Star Wars movie without a lightsaber duel, period. If you think otherwise, you're nuts. Now in order for there to be a lightsaber duel, one of the combatants must either be a Sith or a Dark Jedi, otherwise the duel wouldn't take place. So the formula would look like this: 100% chance of a lightsaber duel = at least a 50% one of the combatants will be a Sith, or at least a 50% chance one of the combatants will be a Dark Jedi. Bottom line: at least a 50% chance of the Sith being in the movie.