There should be a special page web interface for adding wikis easily. It could be quite useful for Wikimedia and other wiki farms. There's the addwiki.php script in maintenance directory, but that requires shell access and thus, at least on Wikimedia, a server admin.

Wikia had a special page for creating wikis called Special:CreateWiki (actually, they still have it, just not on Central Wikia). A user could fill in the "wiki request" there and Wikia staff would review the request and create the wiki if everything was ok. I've googled for something like this, and so far nothing.

Perhaps the extension could use various bits & pieces from config/index.php - that's the basic layout for the installer script which works well...at least when installing one MediaWiki for the first time. ;-)

Version: unspecified
Severity: enhancement