So I've been told. I will try to search for her post, but this sort of info can't appear in too many places, so I'm hopeing she reposts.
I've got links to some of her eyewitness reports from Oct. 1 in the summary at my blog. Check out post #41 for the link. She has done an incredible job for sure.
Continue looking, but the gist of it is that only some gates have cameras, and other than the "donor" gates, those point away from the gates and to the ticket windows, IOW they are there for theft prevention, not physical security. She also reports new cameras going up after the fact. So, it could be true that no video camera caught anyone running away after refusing a backpack search, but the cameras, those that exist all, are not positioned to have caught something going on at the turnstiles (or whatever arrangement they have for taking/checking tickets at the gates).
BTW, she also made a recon pass by the Mosque and the apartment complex where Joel lived, verifying that the old blue Lincoln Town Car was still there as of yesterday, over a week after the event.
Meanwhile here are a couple of her posts on the subject:
http://www.freerepublic.com/focus/f-news/1500193/posts?page=33#33
http://www.freerepublic.com/focus/f-news/1499412/posts?page=98#98