In a DiabloFans interview with Blizzard developers Josh Mosqueira, Travis Day and Wyatt Cheng it has been revealed that 'new features' for Diablo 3 will not be announced before Blizzcon.
While it's unclear what that content might be the Blizzard developers did go into some detail about the changes they're making ot the game.
Changes to the Archon and Wrath of the Berserker won't be made in a "vacuum" which will occur as part of a larger shift in class skills. This is so that skill powers can be more effectively distributed.
Blizzard will be adding the Mystic back into the game though it's unclear what special feature she'll have. It was noted that Blizzard take "some direct ideas" from the Diablo community.
Day revealed that Blizzard doesn't want Diablo 3 to go the eSports route as it's intended as a PvE game and they feel a focus on PvP would distract from that.
Elsewhere in the interview, it was revealed that the PS4 version would not be a launch title for the console and will launch in 2014.
The game was announced for PS4 in February and it will be released for PS3 and Xbox 360 in September. The game launched on PC last year and was initially met by significant problems as servers struggled to cope with the volume of players. The console versions of the game will not require an internet connection.