I have played w/ the 5dIII. (rented it for a vacation trip). This is really for static shots, its tough to do with people in the shot.
It is interesting. I tried w/ several gaps in exposure, 2 or 3 stops seemed the best depending on subject. In DPP (Canon's current post processing software) I have done things like 6, the results are a bit odd.
If you see me with a wrench, call 911
I don't like HDR. I like in-camera-HDR even less. I don't think I'd let that sway what camera I bought AT ALL.
If you want to do HDR's you owe it to yourself to check out Photomatix, it's my favorite HDR software so far.
John.
Amateurs worry about gear, pros about the pay, masters about the light, and I just take pictures!
I think your comparison is about lenses and not IQ of the bodies. They use the same sensors, have virtually the same noise levels and I have not seen any sharpness difference worth noting. The 17-55mm is a cult lens for 1.6 bodies (IS, fast aperture, good sharpness) so I am not suprised that you find the IQ on your 60D is much better. But not because of the body.
Cheers,
John.
Amateurs worry about gear, pros about the pay, masters about the light, and I just take pictures!