There are also some soft shots in the 5D2 gallery as well; namely the turtles, the dog lying down in the woods in front of the tree, the dog in the sun with it's mouth open, the bird on the branch, the Dog with the santa hat on.
I think the 2 best shots in the 5D2 gallery are the first building and helicopter, but after that it's a toss up.
Not including the hazy shot in the 5D3 gallery, I like the dragon fly shot, the buildings with the trees, the dog with his tongue hanging out, the cars.
Besides the first building shot from the 5D2, "I prefer the colors and contrast of the 5D3", specifically; the green grass behind the dog, dragon fly, yellow bike cart, blue sky white clouds and green trees)
It's too difficult to compare different cameras, with different lenses, in different lighting. Heck, just 2 hours will make all the difference in the world when it comes to lighting, and thats with using the same equipment.
If you need the features of the 5D3, then I would go for it, if you don't then I think you might as well keep your 5d2.
Rich