The team mentioned the MMO shooter's revamped progression curve, which has changed to the point that "you will feel the difference." In-game mailboxes, separate chat channels, "rare legendary weapon drops," and clicking-on-player-names-to-whisper are just a few of the features in the works. The game's HUD is now drag-and-droppable, and the crafting UI has a new and less confusing layout.
There's more where that came from, too, so click through the links below to read all about it.
[Update: The official site has updated with a dev blog outlining the Q&A!]