All the editing history is archived, right?
http://en.wikipedia.org/wiki/Wikipedia:Deletion_policy#Acces... says:
Because many deleted articles are found to contain defamatory or other legally suspect material, deleted pages are not permitted to be generally viewed. However, they remain in the database (at least temporarily) and are accessible to administrators, along with their edit history unless they are oversighted. Any user with a genuine reason to view a copy of a deleted page may request a temporary review (or simply ask an administrator to supply a copy of the page). Note that these requests are likely to be denied if the content has been deleted on legal grounds (such as defamation or copyright violation), or if no good reason is given for the request.
But if defamatory material is added to a popular article and reverted away, doesn't it remain in the edit history forever?
Or simply, knowing that it is likely to be deleted puts you off from contributing at all. I know that is one of the main reasons I have almost completely stopped contributing to Wikipedia.
And he's talking about the number of articles, if I'm not mistaken.