As for forums, there is AWC's Forum Extension: http://forums.anotherwebcom.com/vb/wiki.php?page=Category:MediaWiki:Forum Not having used that myself, I'm not sure whether it works with the latest MW version (though I believe Wikia uses it).

HTH.

It might work if you fiddle some. My experience trying the installation script on 1.9.3 is

"Fatal error: Call to undefined function wfProfileIn() in /public/html/wiki/includes/Setup.php on line 23"