The performance of the new sensor really looks amazing. Very low (and pleasant) noise, with superb detail retention. The K-5 output looks like it came from a current-generation full-frame sensor. I agree with those who say that the D7000 photos look worse due to rather horrid detail retention, but in the end I am sure that the RAW output from both cameras will be very similar. If so, Nikon owners should be quite pleased to see these K-5 results, since the new Nikon should be able to do just as well.
It would seem that the pre-announcement buzz about a big jump in APS-C high-ISO performance was not just hype. This is quite exciting.
Dan