Slight correction, though your point stands. You would need to buy the $2,800, 27" Cintiq[1] and a new computer to compete against the Surface Studio offering. This makes the Surface Studio a more compelling offering on the surface, at least to me.
Penny Arcade's Mike Krahulik has been using one for a week and compared it to his Cintiq:
> Tycho asked me to compare it to my Cintiq, and I told him that drawing on the Cintiq now felt like drawing on a piece of dirty plexiglass hovering over a CRT monitor from 1997.
[1]https://us-store.wacom.com/Catalog/Pen-Displays/Cintiq/Cinti...