See: http://www.flickr.com/photos/kyo4890x115/sets/72157627309252250/with/5988317954/
via: http://forum.pentaxfans.net/showthread.php?t=116103 (in Traditional Chinese)
To download the original, click the "View all sizes" button and then select the "Original" size in 7264 x 5440 pixels.
Inspect on the IQ for whatever aspects you like by yourself. I blog, you decide!~
Btw, 40MP seems to be a quite huge number of pixels up till now but it seems that it will be a thing of the past very soon, I'm afraid. It is most likely that the new Sony ILDC and SLT cameras will have new Sony 24MP APS-C sensor with a 4um pixel pitch size. To side track a bit, the diffraction limit for that 4um sensor will be at f/5.6 smallest for the aperture, before the sensor out-resolves the lens, nevertheless. With the same manufacturing process and technology for the same pixel pitch size and density, it will be possible to make a 9000 x 6000 135 full frame sensor which is just a 54MP one in 36 x 24mm and already has more pixels and a higher count than the current 645D body with the old-style Kodak CCD sensor in 44 x 33mm.
Related:-
Comparison of Sensor Specs - 645D Against Others