If you visit a not installed wiki not via script path (http://example.com/w/), but via path created by rewrite rules (http://example.com/wiki/), you will see that the usual "Please set up the wiki first" message fails to display the MediaWiki logo because its relative URL is /wiki/skins/common/images/mediawiki.png. Probably, just link to the mw.org one?
Version: 1.16.x
Severity: trivial