If you can get past this guy insulting the actress, his observation is pretty cool.
http://www.youtube.com/watch?v=U4iPXwSnpFI
I have no opinion on the authenticity of the original video but what I find intensely interesting is the glass. The glass in the store next door is untouched. The glass from the two broken windows has fallen outwards therefore the glass was not broken by the force of the blast it must have been broken by projectiles from the blast. Even so why did the bulk of the broken glass fall outwards towards the blast? Not just outside but spread out many feet from the window. Anyone standing in front of that window would have been injured by the glass. This makes you wonder about the two individuals sitting in front of the window seemingly uninjured. Last there are three people standing in the glass debris field. Normally people do not choose to stand in areas covered with broken glass, very odd.
His mystery about where the extra glass came from is easily solved: It came from the two windows above on the second floor of the building. They were also broken in the blast you can actually catch a glimpse of this in the video and were knocked out later.
As I said I have no opinion on the original video, today there is now way to tell if it real or edited, that is the problem with YouTube. However if the video is genuine it poses some disturbing questions.