Here's the video that I mentioned:
The whole thing is useful to watch, but at least scan through to see two things. First, look for them holding up a print. I forget the ISO and exact print size, but it's pretty impressive. Next, scan forward looking for locker room scenes. Those were shot at ISO 16,000! Even though they're relatively small on our computers and we're seeing a video, I think that the blow away the 7D.
Also, keep in mind that all images shown are in-camera JPEGs. No Raw conversion and no added NR.
Dave