I Think its also quite telling that they found the biggest person they could find (Shaquille) to do the physical showcase. On an average sized person these will be massive, and not just look(and feel) like large weird sunglasses. And no, I dont believe that these where the "large" version, except in the regard of the headband.
I doubt the core unit will be meaningfully smaller.<p>Where in comparison, the HoloLens team seemed to take more care in the design of a large device on a person's head. Looking strange but functional.