Nothing official has come out yet. I'm told that the NHTSA rated the Model S in August 2013--a little more than a year after the first Model S deliveries in June 2012. If it took the same amount of time, that would suggest November 2016. Of course, it could be sooner or later than that. (Other crash tests for the Model S, notably EuroNCAP, were later. The IIHS hasn't done any crash testing on the Model S; I don't know if they will on the Model X, or if they'll also consider that a niche luxury car.)