This could be the final Nintendo Direct, replaced by something similar next year.
In the investors meeting they did say something about how they had some unannounced titles in the works, so who knows, one or more of those could be mentioned here. Twilight Princess HD seems likely. I also expect some more info on upcoming games like Xenoblade X, Mario Tennis, Star Fox, etc., which may show some new details. I also wouldn't be surprised if some more DLC is revealed, and the results of the Smash ballot may be shown. And since this is on a Thursday then there may be one of those things that gets announced and immediately available on the eShop.