Originally posted by lithos I'd say that red square on the bottom left of the lens mount holds both your problem and your answer.
Yeah, what he said.
I think it's the design of the sensor and shake reduction system, whereby the sensor is allowed to free-float. When you're ready to take the shot, electromagnets are engaged that hold the sensor in the correct position; in addition, when SR is on, these electromagnets also move the sensor to compensate for any camera shake. Take the same photo, but with the K7D in the middle of an exposure, and the sensor should look straight.