Judging by the trailer, We Steal Secrets: The Story of WikiLeaks is an admirably balanced treatment of the subject.
If I have a concern, it's that it sounds like there's a lot of splicing in the audio. Understandable, on one level, since the people who put together these trailers need snappy quotes to create interest in the movie, so they remove a lot of verbiage. It's harmless trickery as long as the film-makers do not manipulate the meaning conveyed by the speakers.
We Steal Secrets is a documentary and not to be confused with a WikiLeaks feature film now in production, starring Benedict Cumberbatch.