The home screen icons were the highlight for me. The hardware mockup is full of hyperbole, but the icon set seems very humble in contrast. It is much closer to Apple's established branding than the real (beta) iOS 7. This is the kind of icon set that could be introduced without making all existing icons seem out of place.
And it looks gorgeous on a black iPhone (mockup) because it's not as light.
I think it's what will most likely happen over time - elements and affordances from the old design will bleed into the stark minimalism of the new one (along with new ideas). The iOS 7 design is minimal in order to be a blank slate.
And it looks gorgeous on a black iPhone (mockup) because it's not as light.