The documentary, which is being called Revolution Truth, claims to feature the "images and voices" of both Julian Assange and Michael Moore. The film aims not only to promote Wikileaks, but "interupt the US government's attempts to villainize and prosecute Julian Assange and bring down Wikileaks," according to the film's website.
Though it's unclear if film is directly associated with Wikileaks, Assange does appear in the trailer.
UPDATE: The film's creator, Tangerine Bolen, says that the future of the project is yet to be determined. "It is a short film (yes, MM will be in it), a project, and a global campaign in support of Wikileaks, Assange, and democratic freedoms," says Bolen. The creator/producer also stated that neither Moore or Wikileaks is involved in the production, despite its appearance on the Wikileaks Facebook page.
RevolutionTruth.org has more information on the film. You can watch the trailer below.