As far as 4.0, the final build should hit the PTS soon, with new changes to gems (old gems won’t be salvageable but will be socktable), old buffs will be usable (but not craftable), you can’t get lunarite from sunken treasure, and cargo will see a nerf (to be rejiggered later). Beyond that, Trion doesn’t know when 4.5 will port westward, and the Riches From the Depths event isn’t on the docket yet either. Christmas will land after 4.0, however.
Also of note is that Trion says the ArcheAge remastering announced for Korea last week is not planned for the western version of the game.
Trion also put up a new post detailing changes to the lunagem system as overhauled in 4.0 Maelstrom; the key bit is that they will socket every single time with no chance to fail thanks to RNG that makes you want to punch a hole in the wall.