This is interesting:
Sony did lay off large portion of their IT department last year because of supposed lapses of proper network security protocol. I'm sure there was a disgruntled IT nerd or two amongst the bunch.
ack-ack
... the malware used specifically targeted areas of Sony's network that showed it had to have had prior knowledge from the inside - of course, this could just be another level of hacking, ...
Social engineering (or social hacking), i.e. getting a password from a user by pretending to be the IT department, used to be the number one manner in which organizational data was accessed.