Health potions are one of the core elements of Diablo III, but they’re not actually interesting to stock up on. The game has thus removed them altogether; Legendary potions are unchanged, but you normally just have a bottomless health potion to heal you. The change is simple, straightforward, and as good a lead-in to a patch full of item changes and additions as any.
Legendary rings have been added to the game for players to find and incorporate, and several existing Legendary sets have been altered. The Barbarian, Wizard, and Demon Hunter also have access to new Legendary sets, and several items and Legendary Powers that have been altered across the game (these alterations are not retroactive except in the case of item sets, however). Players should peruse the full list of changes to get a sense of the scope; class abilities have been changed a bit, but the item changes may very well require a whole new approach to the game.
[Source: Patch notes]