That is very impressive. Do you by any chance have any showing how it handles underexposure at that sensitivity? I find this is the huge problem for me with high ISO performance, as a lot of the low light things I have tried involve nighttime street photography. I can often get a nicely lit and exposed subject, but the quality in the dark areas just ruins the image. Here's an example from my K100D, which performs very unimpressively above ISO 800:
This is a 100% crop at ISO 3200. It's a black shelf against my white(ish) walls. The noise pattern in the white I can live with, but the black is just unusable.