I had an interesting experience this weekend with NX2 2.2.6. I took some older high ISO images from my D70s and D200 and reprocessed them.
I also shot a load of images at a saturday evening Halloween costume party with my D200/SB600 and processed the ones I liked yesterday. All were shot at ISO 1600.
In a nutshell, all the images exhibit lower visible noise, I would say nearly a full stop's worth from an appearance perspective.
It appears there is a change in 2.2.6 from 2.2.5 in the denoising algorithm and when it is applied. I can SEE the difference comparing older TIFF files, (I always create a 16 bit TIFF from my RAW files and then print it from Photoshop).
Which gets us back to the difference between the way that the sample images look when viewed with noise reduction turned off in NX2 for a D7000 RAW image. It is clearly being cleaned up when compared to the images that Imaging Resource posted as unprocessed jpegs.
I am wondering if anyone else has observed this. I am also wondering about the results people are talking about compared to their older cameras. I would be curious to see what D90 owners see before/after an upgrade.