Way, way too early to tell. I foresee the X selling quite well in the beginning, but it seems to, so far, be coming at the expense of the S, rather than in support of it. That could change, but I doubt that a ton of people wanting to buy into the One X would instead settle for a One S.
Also, even if the Xbox One does end up outselling the PS4 in the US...does it matter? Until this year, the race between the two in the US has been relatively close and the PS4 is still dominant worldwide. The Xbox One surpassing PS4 sales in America would only upset the balance a tiny bit in MS's favor.