While not the major announcement that many Diablo fans were expecting, Blizzard Entertainment announced that as part of a 20th anniversary Diablo update for D3, that the original Diablo will be fully playable from within Diablo III. This idea isn’t new as it was posted about numerous times on the Battle.net forums. The following was one that was created shortly after Diablo III launched back in 2012.
http://us.battle.net/forums/en/d3/topic/5151718941
And the following was an old post of mine not directly in regards to the above, but a reply to someone elses idea of a randomized dungeon in the game where I suggested a logical entry point to that would be from within the Tristram Cathedral (where it would be a different take on the original 16 level dungeon from Diablo I).
http://us.battle.net/forums/en/d3/topic/7709121668#post-18
Additionally, the parting out of content that was originally slated for the now aborted expansion will continue with two additional zones; Temple of the Firstborn and Shrouded Moors.
The Necromancer class was also unveiled as a class that will be playable in Reaper of Souls in 2017 via a purchasable “Rise of the Necromancer” class pack.
It looks like they are utilizing a part of StarCraft II’s monetization scheme for Nova Covert Ops mission packs as well as pay walled allied commanders. I expect the pricing to be similar for this class pack (which Frank Pearce mentioned would contain some additional content noted in the above Blizzard posting).
Blizzard is obvious not yet ready to announce the actual followup to Diablo III given that they have been and are still filling positions for that particular project. The question is whether or not the above will satiate that part of the player base that is looking for actual new things to do.
UPDATE: Blizzard’s Day 1 Recap