Maybe we also get something like this
Anyone sitting at the Windows of the world eating breakfast. "Hey, that plane is flying wery low. I think i will film it." Then continue to film it until the plane crash into the tower he is sitting in. That guy post it on Facebook and/or Twitter.
Also, there is a chanse that one of the 18 people that found stairwell A in the second tower post something on a social network/newspaper telling that stairwell A is ok at the point of impact and people above the point of impact hear about it and manages to get down that way.
And as the policemen in the first tower hit get the order to evacuate the firemen may still have the lousy communicationdevices, but they might have mobile phones or Iphones with them. Deathtoll in tower 2 was 600 people. That number might be a few hundred less in todays world.
400+ firemen, police officers and other rescue people might be a few people less killed since modern communication can save them.
The people trapped in the towers might also send pictures of blocked stairwells and the destruction from the planes.
If you think the French brothers documentury is eiry with the first plane flying straight into the towers, imagine pictures from inside the towers of it coming towards them