Character portraits have been added to all major characters (Implementing this took most of the time by far but it was absolutely worth it.)
Demeter battle made more forgiving, spore pods, Persephone spawns and spore clouds less oppressive.
Minor bugs and timing hiccups removed, particularly in the XCLIME area (2-B), which had occasional framerate drops before exiting it.
Unequipped dodge tool has the smallest cooldown before dodging can be done again (0.1 seconds)
Death Claw sidequest stage (FWS Nocturne) added
4-A Orbital Elevator stage added
On the whole, this update is a few major things rather than a lot of small ones.
Here is a YouTube supercut of the game, mostly comprised of highlights from live playtesting on Twitch:
https://www.youtube.com/watch?v=-kjiuGWIEAs
Update 11/14 10:54pm: Linux updated to 1.9.0
Update 11/17 1:18pm: Mac updated to 1.9.0