WikiLeaks -- Does it really expose ALL government secrets?

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I know it shows us what our world leaders think about each other and how they feel about certain political issues taking place right now. But on a deeper note, not to sound silly or like a conspiracy theory freak, but does WikiLeaks expose any juicy debated secrets like Area 51/Roswell incident? Secrets regarding life on other planets? Any secrets surrounding JFK assassination? Anything like that?