I'm not inclined to believe anything regarding Wikileaks or Assange. I'm sure more than a few people have seen those tweets and some Twitter crawlers/indexers have them stored somewhere. We'll see how it plays out, no need to speculate at this point.
Wow, a conspiracy theory that would make sense. The US government finds the leak in may, knows wiki leaks has it. Knows that they'll not be able to directly attack the organization on free speech grounds so they create a character assignation plot and create a rape plot.
And a more recent follow up: http://rixstep.com/1/20101202,01.shtml