So long as we're posting pictures taken in the dark of our cats...here's Baihu the evening I got the 5DIII. 85mm @ 1/4s @ f/1.8 @ ISO 25,600, and then about another stop altogether added in post...call it EV -6, handheld. The main light is from the LED on a battery charger about six feet to his right. The rest of the light is coming from that computer monitor several feet behind him in the top of the frame.
I don't remember how I got this in focus, as I really couldn't see a bloody thing.
That the camera can make pictures like this in settings where a human is blind...well, I'm sure not going to ever do this sort of thing other than on a lark, so I'd say that its low light abilities are much more than I actually need.
Anybody else who needs more than this needs a head examination more than they need a better camera....