7d latitude and shadow detail capabilities?
 

How about some comments on the latitude and ability to look in the dark on this clip
YouTube - Canon EOS 7D sample video

I have no opinion on the technical aspects of this clip, but I would like to point out that the subject is a well-known and quite well-received street performer in New York. My wife and I had the privilege of catching him in this same Central Park tunnel way back in July of 2003; nice to see that he's remained true to his style after all this time.

For those who are interested, his web site is Thoth - I heal through divine prayformance

I think you mean dynamic range (distance between highlights and shadows), not latitude (flexibility to over- or underexpose). In that shot the dynamic range is very poor, but I would guess that it was used with default settings. The default settings are optimized for high contrast and low dynamic range.

Hard to say, but I've had problems shooting in environments like that with an EX3, just seemed to camera wasn't forgiving enough to capture that extreme a range of lighting conditions.

It wouldn't be a good shot even with more dynamic range. We would just see more dark detail which wouldn't contribute anything.
If the performer would step forward and if the shot were framed tighter it would be better.
I know that's not what your asking, but more dynamic range is seldom a real benefit to better images.

That clip was obviously shot with the default color settings. You need to shoot "flat" to get more dynamic range. I do so for all my cameras, including still cameras.

Why do you think it wouldn't contribute anything? If you mean revealing what's in the shadows, that's a benefit, because it's more information.