Re the video, the sound didn't work the first time I played it. After the comments above I played it again and heard what people refer to.
There are, however, a number of odd factors. First of all, inside the aircraft. If this was taken immediately after the crash, before the emergency services arrived, where aqre the trapped passengers? I watched the live coverage on two stations together, BBC 24 and Sky News. Discounting the repetitive loop footage, a number of persons were being removed from the aircraft centre section at least an hour after the crash. The footage showing views in each direction inside the cabin shows only a handful of people moving around in quite a leisurely manner.
Why is the camera user staying inside filming?. The instinct is to leave the aircraft as quickly as possible due to danger of fire. All evacuation instructions tell pax to get as far away from the aircraft as fast as possible.
All previous survivable accidents I've ever seen footage of, read about and actually witnessed have been the same. The pax, even if stunned, evacuate as fast as they can, often in panic. They don't linger near the aircraft unless they have lost mobility and, whilst during the Toronto A340 accident a couple of guys did use camera phones the panic, rush to evacuate and movement away from the aircraft is in complete contrast to what we have here.
The middle segment has people wandering around close to the aircraft in a relaxed way. There are people in orange jackets visible and the guy in the blue jacket looks totally unconcerned. If they are pax, would they have had time to find their jackets and put them on before leaving the cabin?
The sound quality, if this was a mobile phone, is excellent but seems almost too good - as if it has been added later as the sounds during the outside shots have the same resonance and acoustic as those heard when the camera is inside - which is odd as is the fact that the shouts, obviously from inside, are being so well picked up whilst the camera is some distance from the fuselage.
Could this have been taken by a member of the clear up crew and someone has added the soundtrack for effect?