I was shooting at a equine event yesterday (Cross country) so I was able to put my new 40D through it's paces. using tracking focus I was able to test the timing (read shutter lag) and the frame rate for capturing a galloping horse.
it did rather well.
I waited until late in the day when the sun finally put in an apperance around 4pm, and the intensity was really nice, soft shadows and in exactly the right place for the jump I had selected for the final class.
The biggest difference was in the colours, using the same resolution, settings as the mk2N, and the same lens (swapping between bodies) the greens and brown's looked far richer before any PP was applied.
So in a far from scientific test the new 14bit colour depth of the latest canon's (40d, 1dmk3, and 1Dsmk3) seems to make a difference, and for me when I'm working outside browns and greens make up a significant part of image
it's not a chesnut horse, but it does show the richness of the greens, and the tonal range achieved by the camera as there are some dark shadows in the bushes, yet the grey (white) horse and flags have no loss of detail
settings wise - it's as supplied by canon with regards colour space and picture style, with an ISO of 500 and in Av mode f4.0 (70-200 2.8L) AWB, eval metering
I'm happy to see Canon, with their in-camera settings, has gotten back a bit of the color magic that made their first 1.6x dSLR (the D30) so wonderful.
Somewhere along the way I think the "pixel peepers" got all excited about "accuracy" and forgot that the imagery actually needed to look good, and this influenced Canon's tuning somewhat. Some of the color decisions (e.g., in intermediate models like the 10D) were questionable in my opinion.
Of course, Raw shooters have always been happy to dial in their own tweaks.
Funny thing, though... Raw images from the 40D are coming out pretty darned nice also - a visual cut above the predecessor models. The response of the imager itself and the 14 bit conversion really do make a difference.