Actually we are experimenting with the Rift and a Motion Simulator. Too bad the SDK or runtime doesn´t give you the control over tilting correction.
Though this should be possible with the camera but they are only measuring and correcting the pitch/roll difference between the Rift orientation and the accelerometer once in a second (or two).
So we have to correct the angles with an external sensor, which is working but would be better to get native support for this. Oculus did not respond if this is planned or actually possible for them.