http://youtu.be/zGp5dkJdi0wNew hero: The Crusader, meele character with shield and swords / flails (i.e. Paladin).
One new Act: Supposedly much more of a "dark feel"
New level cap (70): new skills and runes.
Loot runs: Entirely randomized dungeons that take 15-20minutes to complete (for endgame).
Expanded paragon system: Paragon levels are now account wide (applies to all characters), no more cap.
Loot 2.0: Modified loot-system, guaranteed legendary drops from first boss kills and a new system called "smart drops", loot will drop less but the drops will be better and more meaningful for you.
Transmogrification: Change the look of your stuff but keep the stats (see WoW).
The Mystic: Artisan that allows you to re-attribute the stats of your items.
Story wise, it's the Angel of Death messing things up : Takes place in Westmarch and it takes influence from western Gothic locations, more of a medieval setting.
Random tidbits (mostly quoted from
Eurogamer's live blogging) :
Playable on the floor at Gamescom.
No release date announced so far.
Comparing original D3 and the expansion :
- in Act 3 you'd find 256 common, 399 blue, 275 yellow and one legendary.
- In Reaper of Souls, it could be 73 white items, 266 blues, 83 yellow items and 6 legendaries (they will be "build changers", example with wizard weapon: summon more hydras)
Gameplay trailer :
http://www.youtube.com/watch?v=zGp5dkJdi0wCinematic trailer :
http://www.youtube.com/watch?v=Cb7QJwQ58T0Stolen pictures :