What I think is gonna be revealed:
-6.0 title with a well-hidden hint to beastmaster on the side
-5.5 nier and ultimate raids (ultimate I'm not 100% sure honestly)
-new and final trial (+extreme version) of shadowbringers
-the firmament completion+explanation on how the new houses will be distributed to the players (if we get some sort of priority system for those who contributed the most?)
-probably new stickers and other stuff for the gpose

that's it, if we see more I'll just take it as added bonus