The New Number One, tOP article.
Calling its dynamic range performance "wonderful," DxOmark says this area is "clearly where the K5 struts its stuff...even the [Nikon] D3X’s full-frame sensor is not [as] good."
Apparently the new Pentax K-5 has the best-performing sensor in its class, by far. Given this, and the excellent hardware and in-body image stabilization, I will say that David is Kicking Goliath solid around the playground, comparing to the much, much larger companies, Canon, Nikon, and Sony. This is remarkable.
And the value-for-money is outstanding too. In the semi-pro market, that is. In the serious-amateur camera market, the K-r and the K-x are at least as good value-for-money.
It turns out that the autofocusing in Live View mode is one of the fastest yet, so that this is useful not just on a tripod, but for hand-held shooting too. This is great, because it can be very handy to hold the camera near the ground and over your head, and still use autofocus (on the screen).
Also, the ISO 6400 is actually useable, in my estimation, which must be a first for APSC-sized-sensor cameras (not full-frame). Impressive.
And it shoots at 7 frames/sec, if you need it. Dang impressive camera.