This is apparently well known to people who've been following the story closely (Michael Parenti, who's been very helpful with all this, was gently laughing at me on Twitter). But it's still fascinating. What it means is that the potential flow of online information to WikiLeaks, the organization's reason for being, is shut off. If you visit the group's online submissions page there is still a bullet point on "our anonymous electronic drop box" that "Its (sic) easy to submit" to.
The site explains "we have created our novel method of submission based on a suite of security technologies designed to provide anonymity. We have put a great deal of technical and design work into the drop box because we take the journalist-source relationship very seriously."
But if you read on, you find that it's "currently closed for re-engineering security and useability concerns." The secure chat function for submitters seeking advice and the "secure upload" function are likewise shut. Desperate to leak? "Post your information to one of our trusted truth facilitators listed below. You may post to whatever country in the list that you feel most suitable given the nature of the material and your postal service."
That might better be written as "you can send the information to whatever country you like, as long as it's Australia." The only "trusted truth-facilitator" on the list is a PO Box at the University of Melbourne.