I am almost sure that the sample photos should originally be sharper, but unfortunately the tester used the Av mode and deliberately stopped down to f/8 something and thus the final pictures are now looking rather soft and blurry! Well, I suppose the tester just used to use his camera as he was using an APS-C or m4/3 camera (for most of the time probably), but however that time he wasn't! :-o
http://www.dcfever.com/cameras/viewsamples.php?set=672&picture=6095
Click on the thumbnails to view the full-size originals, the key EXIF data are also posted per picture page.
After all, it's the diffraction limit that comes into play, which is the real limiting factor of such a small sensor used in the Q (and any other DCs). So, nothing can work against the Law of Physic and the only workaround is to use the lens wider opened (and with a much faster Time value/shutter speed to cope with). Nevertheless, using a wider Av will yet be a non-issue DoF wide as it has more than enough DoF already for the small lens opening based on the small sensor size and image circle.
At the end of the day, why most Q testers won't simply use the P mode for shooting? In fact, I've noticed that the P mode of it will try to only moderately stop down the lens and thus avoiding the diffraction effect as far as possible, whilst obtaining a little bit better optical quality out of the glass.