Consider this.
You walk down your favorite street/forest/museum/etc and
see the scene that you'd like to capture. You bring your
camera to your eye and do whatever you think has to be done: focusing, exposure, actually composing the image. You click the button.
Light goes all the way through all the glass pieces of your
lens and strikes the sensor. The file is written on to the memory card. Later on you download it to your
computer and spend your time tweaking, processing, editing, modifying the photograph until you're satisfied with what you see.
It seems to me that camera although important is not the most significant part of this process. It is just one of many components, so to say.
I humbly suggest that you consider what I wrote and think about it a little.
Given that both K-7 and D90 are modern DSLR of medium to high class, I suppose that they both will give you great many wonderful photographs. But you'll have to solve the above equation on your own the way you like it. Noone can really do it, but yourself.
I am sorry if you expected a technical answer, 'cause it is extremely difficult or almost impossible to provide one that would be objectice and unbiased.
Last edited by Boris; 01-18-2010 at 06:05 AM.