The visual editor is now available on all wikis using only one language script. 
Changes this week
The new version of MediaWiki will be on test wikis and MediaWiki.org from November 1st. It will be on non-Wikipedia wikis and some Wikipedias from November 2nd. It will be on all wikis from November 3rd (calendar).
Now you can use autocomplete for page names in "Preview page with this template" field when editing templates.