http://www.cnn.com/2014/03/24/world/...html?hpt=hp_t1
Obviously, still a lot of questions to be answered.
Catastrophic decompression that rendered the crew unconscious?
Deliberate action on the part of one or more of the pilots?
Hijacking?
Massive systems failure?
Assuming the debris found is indeed the missing 777, only the FDR and CVR will yield up any firm evidence as to why.
Prayers to all the families, this has to be the worst thing anyone could have to deal with.