That's what I suspected, although I thought the last one was the 7D.
Here's my problem, I keep wanting to just get the 7D but to me, I can see actual image quality difference between the first two and then the last shot. The first two just look much cleaner/sharper. It's a small difference but it's huge at the same time.
I think I'm going to end up getting the 5D MKII when I go to get a new camera, to me it seems to edge out crop sensor cameras.
I notice now the first two are dated 2008 and 2009, then the last one is 2007. Is it possible the picture quality difference is just from you getting better at post processing or is all body? Or perhaps lens?