I'm with blacksheep here. While the crew were perhaps doing this in anger for the first time, they are trained to do so (an earlier comment from an afronted pilot stated they are trained to do it in their sleep - exactly I say!). As an engineer I am trained to fix airplanes. I don't go patting my self on the back everytime I cure a snag and get the a/c on it's way. Pilots and engineers are not there for when things are going well but for when they go wrong!
Enough thread creep.
What we have here is very interesting from an engineering perspective. It is a failure if the pressure vessel, perhaps originating from a lap joint in what looks like the area of a previous repair. Lap joint scribe lines are a know issue with other Boeing types with (IIRC) at least one example being attributed to manufacture rather than maintenance. Of course the previous maintenance history of the a/c will be checked and I personally wonder what disassembly and prep was required for the initial (scab) repair. There are at least 2 frames missing. Were these replaced at some time and failed at their splices?
Also to further confuse the impact/explosive decompression argument. Some of the structure which has blown outwards does indeed appear to have its outer edges curled inwards!!!!
I await the report with interest>