That video shows Phosh on a larger display, which is fine, but it's still just the phone UI blown up onto a larger display with floating windows. I've used it, it's okay, but in its current form it's not something I'd want to use long-term on a laptop or tablet.

The UI shown in that concept art is still just a concept. The notification center and calendar that slide in from the sides, the combined tray/clock/launcher bar at the bottom, the touch-friendly tiling - none of that exists yet.