It's the specific high-ISO noise produced by Pentax's DSLR's that is one of the attributes that keeps me with Pentax. Yes, I'm an old fart from the days of B&W film and I just don't want my images to look like screen grabs from a high definition TV.
Here are my thoughts in a previous thread about why I love Pentax:
"I know I am alone but I will be sadly disappointed if the K7 high-ISO performance is on par with Canon or Nikon. Yes, I know, I can always add noise or digital "grain" to an image but, to me, that's like sucking and blowing at the same time. After 30+years of shooting film, I'm no fan of absolutely smooth, plasticky high-ISO images. If I shoot at ISO 800 or 1600, I want my image to show the imperfect character of those sensitivities (can you tell I don't shoot for stock agencies?!)."
As for making equipment purchase decisons based solely on DXOMark scores (or any other printed specifications/ performance rankings), let me use the car analogy. Who here would a buy a new car based only on a spec sheet and a magazine review? Surely we all test drive the new car we are thinking of buying.
I will be "test driving" a K7 when my local dealer has them in stock. If I like the dreadful
image noise it produces, I'll keep it. Until that day, I'll be enjoying my K20D and the images it produces rather than sitting here wringing my hands about whether or not the competition has a "better" camera than the K7.