Don't get me wrong ... it looks very cool, and it awesome to see something posted.
Like Andrew, I noticed that it does not maintain a centralized axis throughout it's tilt, and I wonder if this type of device would really be adopted for simply turning the camera to a 90 degree position.
There are already some great ways to mount a digital camera sideways (Deadly Calavera, L-Bracket, Red side handles) for increasing usable resolution while shooting green screen effects.
Still photographers rarely switch back and forth from portrait and horizon on a tripod. More often you see that on a monopod. Otherwise, most of that is done while the camera is in hand.