Wikimedia has a new backup data center in Dallas. Because of planned work on this, you will be able to read but not edit the wikis for a short period of time on both 22 March and 24 March. This could be postponed to April 18. You might lose edits if you try to save during this time. Because of a test, there will also be a couple of minutes where you can't edit the wikis on 15 March starting 07:00 UTC. You can read more about the server work. There will be more notifications and updates about this.
Administrators and other users with advanced permissions will need to have an 8-byte long passwords. This change takes place on 15 March. Users with too short passwords will be asked to change password the next time they log in. This was decided in a discussion on Meta and is because they can use tools that can hurt the wikis. 
The new version of MediaWiki will be on test wikis and MediaWiki.org from 15 March. It will be on non-Wikipedia wikis and some Wikipedias from 16 March. It will be on all wikis from 17 March (calendar).
The buttons in interfaces will be simplified. Instead of white, red, green and blue buttons, in future there will only be white, red and blue ones. 
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 15 March at 19:00 (UTC). See how to join.