A couple of days ago, it was noted (on HN) that users were proving it was potentially possible to view and edit other user's files, in other ACD accounts.
Now, the App has disappeared from auth'd Apps in the ACD web console, the "Issues" has been closed on the project's Github, and it continues to not function.
If there's a possible silver-lining, it's that acdcli calls are still returning (in HTML form) a message about "This application is temporarily over its serving quota. Please try again later." which could potentially suggest that the outage is related, but since the ability to view other user's files still exists (and the fix of obtaining your own Developer profile is limited, as Amazon have closed invitations), this could well be the end of the acd_cli project :(
https://github.com/yadayada/acd_cli