According to JJ Abrams, Kylo Ren is not a Sith.

We’re not saying that Kylo Ren is not Sith; JJ Abrams is saying that. We’re just messengers.

What?! How can that be when he has a red lightsaber, black clothes and a metal faceplate? He’s got Sith written all over him!
But if JJ says it, it’s probably true. What with him being in charge and all that.
The really interesting thing though is what JJ told Empire Magazine about The First Order, who they are and what they stand for now. His answer:

“That all came out of conversations about what would have happened if the Nazis all went to Argentina but then started working together again?’” Abrams reveals.

“What could be born of that? Could The First Order exist as a group that actually admired The Empire? Could the work of The Empire be seen as unfulfilled? And could Vader be a martyr? Could there be a need to see through what didn’t get done?”
Makes sense, and with that image of the smouldering Darth Vader helmet in the trailer it fits in. Kylo Ren obviously has a Vader shrine in his bedroom surrounded with a few photos.
But please Kylo Ren – don’t kill Han.