The only clues are Wikileaks founder’s comments on the subject:
“I think it’s better that we don’t comment on that,” Assange said, according to the network’s transcript of the interview. “But, you know, one could imagine in a similar situation that it might be worth ensuring that important parts of history do not disappear.”
Source:
http://www.google.com/hostednews/ap/article/ALeqM5gKu1DQoewmBy2do5ctRqUX5efGBAD9HDFADG0
file download:
http://thepiratebay.org/torrent/5741985/INSURANCE.AES256_WIKILEAKS.SECRET.DOCUMENT.2010.08.06


