I does rotate. The advantage with the Crown Graphic is that the Grafmatic can be attached directly to the Crown's back with the Gralok clips after removing the ground glass/hood assembly. This makes the camera much lighter than the Busch Pressman for handheld use.
It's also a little thinner in the body, allowing use of slightly shorter focal lengths at infinity focus. Not a big factor compared to the weight saving unless you're into very wide angle...