A month ago Zachary Quinto posted a selfie to his Instagram account. It's him in a make-up chair, getting all done up as good old Dr. Spock. Nobody paid much attention to it, or to the blue smock he was wearing that was clearly there to protect his costume from make-up. After all, look how high the collar is! But now, with the release of ScreenCrush's set photos and video, we can see that Quinto was actually showing off the brand new Starfleet uniform.
Let's take a closer look at that picture, courtesy of TrekCore:
You can get a good look at the higher collar, but still with the black undershirt - I'm not sure why the undershirt and the tunic would be so high-collared, but here you go. This picture was taken before they affixed the Starfleet symbol to his chest, or maybe Spock is wearing a version of the tunic where the symbol is elsewhere? That could be a dress uniform, as seen in Journey To Babel in the original series. It's hard to make out here, but the insignia is actually on Kirk's BELLY, to the right of his torso (facing us):
That is, of course, one of the many costume changes over the course of the three seasons of The Original Series. The Alternate Reality movies changing up their uniforms fits right in line with that.