The DxOMark of the K-r has been out. It gets an overall score of 72.
Below are some of those endless comparisons, using the "compare" tool at the DxOMark page:-
K-x Vs K-r Vs K-7 (Well, the K-x has slightly better high ISO noise and very marginally better DR..)
A33 Vs K-r Vs A55
K-m Vs K-r Vs K200D
D5000 Vs K-r Vs D3100
550D Vs K-r Vs 60D
and so on.. that you can compare endlessly till the end of the world! ;-) There is no K-5 comparison though as the DxOMark for K-5 hasn't yet been out. :-(
Besides, here is an ISO comparison on the same scene with pics posted in full sized, but compressed and without EXIF:-
http://www.pentaxforums.com/forums/pentax-dslr-discussion/120750-k-r-iso-test.html
So, happy measurbations after all!
Related:-
K-r Vs K-x ISO Measurbations (Head to Head)
My K-r First Hands-ons (Tested Twice)