Marksphoto: pictures look ugly, skintones are gray and lifeless. Looks as if there was a piece of transparent plastic placed in front of the lens while shooting.
another reason to shoot raw and if you are a raw shooter the upgrade from Mark 2 is irrelevant.
I can't tell the difference in image quality improvement. I can do the same in jpeg mode with 5D Mark2 and just tell everyone I shot it with the new camera.
I have to agree about these photos, they're pretty bad. I upgraded from the mark ii to the mark iii and honestly, I don't see much difference in image quality. I'm sure people will find differences, but I'm getting the same class of prints that I got with my mark ii. I don't generally shoot above 3200 ISO and I rarely shoot that high, so I can't really comment on the improvements in extremely low light. If all I was looking for was a significant bump in IQ, I'd be sorely disappointed.
That being said, the mark iii is so much more versatile. It is a completely different shooting experience. For me, the AF, shooting speed, and build quality really do make a difference in everyday use. I'm a little bitter at the price increase, but I'm really happy with the improvements. If these things aren't worth the price to upgrade to you, then I think the mark 2 is a perfect choice.
PS - I don't shoot video either, so I can't comment on any differences in video quality.