I found all of my attachments gone on my site after a day or so's crawl by google.
With some testing I found that it doesn't care if you are logged in or not, anyone can delete any attachment.
I also notice that all of the images on the mojomojo.org site seem to be missing :-/
Voting on Ideas
Vote for your favorite ideas by clicking on the up arrow.To undo an upvote, simply click the arrow again. This second click removes your vote.