This one contains a lot of engine improvements backported from AVWW. Rendering is now more efficient, and in theory a lot of the textbox issues should be dealt with now.
There's also a bunch of little fixes to recent stuff like the energy rework, drones, and the line-place context menu. And some balance changes to carriers and turrets that should make defense a little more pleasant from the human perspective.
But (and here's the reason for the release name) the majority of the work that's gone into this release isn't even in the notes or visible in the game, because it went into the framework for the major feature of the upcoming expansion. Still not ready to talk about it, but it's coming along well.
This is a standard update that you can download through the in-game updater itself, if you already have 4.000 or later. When you launch the game, you'll see the notice of the update having been found if you're connected to the Internet at the time. If you don't have 4.000 or later, you can download that here.