... allerdings kenne ich so euphorische Meldungen in div. Foren von early
adopters. Ist meist nur heiße Luft ...

I received an ISO 80 DNG raw image from one of the Beta version cameras at Photokina. This contains a strip of 10 black masked-to-light columns at the left edge of the image in landscape orientation which for this particular sample was offset by about 69 14-bit levels, meaning that the black read noise was not clipped to zero at all and the standard deviation was therefore not affected by such clipping. The standard deviation of these black level columns averaged about 1.1 14-bit levels, meaning that the DR for this particular sample in these particular conditions had a value of 16383 (14 bit maximum) : 1.1 or about 13.86 stops at ISO 80 for 16.2 MP on an APS-C sensor in DxOMark terms. This means that the "standard rated 8 MP equivlalent" DxOMark DR score would be about 14.36 stops, and makes the K-5 potentially the current low ISO DR king of all cameras measured so far.  If these results are solely a function of the sensor, it is very likely that Sony and Nikon models using a similar sensor will have scores something about the same.

This means that these cameras can indeed use a 14-bit raw output file effectively, although it must be noted that these extra bits will only be of any use for ISO's below about ISO 640 and then only for the very deepest shadow details darker than about 10.7 stops below the bright clipping level. For brighter tones and/or for higher ISO's, the extra bits do nothing but make the resulting raw file sizes larger.  

... ziemlich blöd für die Hersteller, aber natürlich gut für uns