We already know that the Nikon D90 has both Lateral Chromatic Aberration Correction and Peripheral Illumination Correction features built-in, thanks to the "L" series firmware found in the Nikon D90.
However, what I don't know till today is this - our Nikon D90 can also perform both pin-cushion distortion control and barrel distortion control right from within our Nikon D90 Retouch Menu. With Ken Rockwell constantly preaching about the above distortions, I think its about time we input this information for better image results!
Now, for best results, we ought to now shoot RAW (NEF) that the post processing be done with minimal loss and best result. Wow, I am surprised I can still be surprised with my 8-month old D90. Personally, I would recommend the "Auto" of such distortion control and leave it to the camera to work it out. Indeed, based on the RGB histogram, the picture has indeed been "worked" on.
Amazing...