I've posted a 1Ds3 mini review on my workshop site.
Jack, thanks for posting your impressions. It is helpful information for many people for planning their equipment path forward.
To be bluntly honest though, I don't like the sharpening applied to the image crops. It's just my personal opinion, others may have other preferences. The sand in the roof shingles doesn't look like sand at all, something I have not seen in other reviews before (where material surface texture looks natural). Perhaps they look better in print than on screen.
I was also a bit surprised that you didn't notice the larger viewfinder image (0.76x versus 0.70x magnification for the 1Ds2), where other reviewers specifically mention the bright large viewfinder image. Maybe it was not important enough for you to immediately notice it, which is fine (different strokes for different folks), but it can be important for others (e.g. manual focussing in dimly lit locations). Maybe the difference is obscured by additional info in the viewfinder?
I'm planning to get a 1Ds Mark III myself (when I can get it for a more decent price in Euros), so I'll use your observations as well as the observations by others to complete the list of features I need to test for optimization. The AA-filter characteristics and associated sharpening are high (they moved up) on that list.
Thanks for sharing.
Bart
The 1DsIII is already or close to challenged with its tiny pixels at f8.0 for softening due to diffraction limits.