Blizzard has detailed some of the major changes coming to Diablo 3 in patch 2.0.1, which is currently still in development and available for testing on the Public Test Realm. Highlights include the ability to form Clans, Cursed Chests events, changes to item stats and drops, and a completely revamped difficulty system.
The original Normal, Nightmare, Hell, and Inferno difficulties have been replaced with a "dynamic difficulty," which allows enemy levels to scale up and match your character. Players can still select from a total of five new difficulty settings: Normal, Hard, Expert, Master (which unlocks at level 60), and Torment (which unlocks at level 70). Torment also has a difficulty slider, offering another six adjustments that finely tune the type of punishment you're looking for.
The Clans feature allows players to create or join a Clan with a private chat channel, News & Info tab, and other features you'd find in any other MMO. You can only be in one Clan at a time, but may join multiple Communities that can be set to private or public, giving you more opportunities to find like-minded players.
Fans of isometric role-playing games will recognize Cursed Chests events from games like Torchlight and The Incredible Adventures of Van Hesling . Interacting with certain chests will trigger a variety of challenges, either waves of monsters, a timed event, or a boss enemy. Successfully completing the challenge will, of course, reward you with a Radiant Chest filled to the brim with shiny loot.
Blizzard's patch notes, which you can find here , have a lot more details on changes made to crafting, the Paragon leveling system, itemization ("Loot 2.0"), and other changes, but are not complete yet. For example, all classes have undergone "significant revision," but Blizzard said that additional details and patch notes will be made available later, after more development and testing.
It's worth keeping an eye on Diablo 3 in the coming months if the water cooler talk around its issues has kept you away so far. In addition to what sounds like the game-changing 2.0.1 patch, Blizzard is currently beta testing the Reaper of Souls expansion, and preparing to get rid of the much-maligned auction house . It sounds like it's going to become a much different and much improved game when compared with the version we saw at launch.