There announcement was made in 2 parts, a 7 minute trailer and an interview with the lead devs.
The 7 minute video tells us:
- "Maps were made more rewarding", but he also uses the word "balance" which makes me think that some rewards have been reduced.
- There are now 5 possible tower map layouts instead of 1, 4 new layouts added and the original layout is reworked.
- Boss spawn rate has been increased with the intention of 1 boss per 4 maps.
- Introducing a Boss precursor tablet to add bosses to maps which do not have them.
- Strongboxes open more quickly.
- On death monster mechanics have been made more visible.
- Zoom out further on the atlas and faster atlas load time.
- Omen drop rate increased by 60%.
- Citadels are now visible through the fog by a beam of light.
- Arbiter of Ash boss now gives you 6 attempts to kill it per fragment set, previously 1 attempt.
- Copper Citadel boss has been made easier
- Buffing leveling unique items. None the previews they showed looked interesting.
- Fixed a bug where tier 5 unidentified rares were blocking some mods, such as max tier life on rings.
- Socketed runes in items can now be overwritten with other runes.
- Item filters are now available on console systems.
- Effectiveness of the armor stat has been improved.