From MS curmudgeon Paul Thurrott (who also has issues with The Hinge):
preorders for Surface Book are higher than for any previous Surface device
The issue with the hinge will be if it’s stable on an airplane or train. If it vibrates the display that will be an issue. But for a first version this thing looks amazing. Surface pro is the tablet that replaces your laptop. Surface Book is the laptop that replaces everything :-)