The new version of MediaWiki will be on test wikis and MediaWiki.org from 13 September. It will be on non-Wikipedia wikis and some Wikipedias from 14 September. It will be on all wikis from 15 September (calendar).
You can join the next meeting with the VisualEditor team. During the meeting, you can tell developers which bugs you think are the most important. The meeting will be on 13 September at 19:00 (UTC). See how to join.