I see a lot of support requests from people who have evidently just installed an old version of MediaWiki. Why not make the installer check what the latest stable version is (by looking at http://www.mediawiki.org/wiki/Template:MW_stable_release_number, maybe?) and complain if the user is installing something out-of-date?
This check should probably fail silently if it can't connect to mediawiki.org.
Version: 1.15.x
Severity: enhancement