I'm working on a cross-WMF-wikis spam list with a few stewards, which sadly has a huge data corruption because of the iso-latin the original dev (Beetstra) used in the database instead of a plain UTF8. We've been trying to correct it, but we're hitting a problem when it comes to get the page title of revs that have been deleted : it's impossible. (end of "my life message")
In the user interface, Special:Undelete uses a timestamp instead of a rev id, and requires a page title, and allows to see the contents and comments.
In the API, &list=deletedrevs provides similar information.
The problem is some links are provided with nothing more than a rev_id (especially when shortened, "/wiki/?oldid=12345" for instance)
It should be possible to get the page title and perhaps other properties of a deleted rev by providing only its id.
It could also prove useful to alter Special:Undelete to use revids instead of timestamps, seing as timestamp seem somewhat "messy" (there's always a possibility for two edits to occur in the same second for the same page).