Lots, battles are no longer restricted to 3v3, they are fought in open space.
There are also new items such as deployable turrets and shield generators. Deployables last a set amount of time but don't require you to be nearby, you can drop some turrets around an Outpost for some extra defense while you head out into space.
More is planned, but it is best said in a blog post so I will give more information when I have more to show.