Uploaded files which are deleted can now be undeleted; admins can also view the deleted files without actually undeleting them. This is integrated into the existing Special:Undelete in what I hope is a fairly clear and intuitive manner.
It's my hope that this will encourage admins to tackle the deletion backlogs a little more aggressively, since mistakes will be easier to undo.
I've tested it both offline and on the live servers and everything seems fine so far, but if you do encounter problems please report them at http://bugzilla.wikimedia.org/
-- brion vibber (brion @ pobox.com)