I've been rather overwhelmed with non-wiki work recently, so I'm way behind on my mail. I noticed the tarball announcement, and I think you'll want to modify the tarballs slightly to remove the user subdirectory.
The reason to remove the user subdirectory is that it contains the user cookie data, including the "randkey" value which validates the user cookies. With these files users could impersonate other users and have the same UserID number. This probably isn't a big deal, since I don't think too many people are looking at the UserID numbers (which appear in the popup when you move the mouse over a username in RecentChanges).
Probably the easiest way is to use the tar option to exclude the user directory. Another approach would be to move the user dir and change the $UserDir variable in the wiki.
I hope to get less busy in the next few weeks, and help out more with wiki issues. Wikipedia has definitely exceeded my expectations--thanks to you and all the other people at Wikipedia/Bomis.
--Cliff
There is now a tarball of each of the wiki sites that are running as "Wikipedia". Go to the homepage http://www.wikipedia.com to find the link, or go to the downloads directly at http://www.wikipedia.com/tarballs. These are just tarballs of the entire directory that the sites are served from.