This was actually a blend of two exposures. The center (the moon itself) was shot at 1/1250s f/3.2, whereas the rest was shot at 1/10s f/3.2. The blended exposure matches quite well what I saw with my eyes, which is a dramatic case study of how adapt the human eye and brain is to dealing with huge differences in contrast or brightness.

Please note that a carefully calibrated monitor will be important to viewing this image. Make sure that you can distinguish all the shades (especially X,Y,Z) on the following image from dpreview.com: