This MediaWiki page is inactive and kept for historical interest. It may document extensions or features that are obsolete and/or no longer supported. Do not rely on the information here being up-to-date.
Several extension pages are long overdue for review. Many are lacking the appropriate tags, both header and within the extensions, which cause confusion for other developers and sysadmins. In addition to time wasted on bad installations, there is also time wasted by other developers providing tech support to these bad installations. The 2012 Extension Page Review Drive is an effort to check for proper tags, headers, templates, status, etc. on every MediaWiki.org page documenting an extension. This page has been setup to recruit volunteers for the page drive and track their progress.
This effort will also help with future drives reviewing actual code of extensions (although you're welcome to do thorough code review during this drive if you'd like) and moving extensions based in wikicode to the code repository.