Some early info provided by stunedge through his twitter...
Each character has two version: Normal and Shadow. Shadow characters have no burst but have access to something called "Shadow Fury".
Yu can no longer do Sweep xx 5D
Akihiko Cyclone goes up to 5 now.
Kanji's 5C paralyzes the opp
Yukiko has a new move and a new super which is lv6 only (wtf)
Characters have different amounts of persona cards, Akihiko has 2, Yukiko 5, Yukari has 4 and Elizabeth has 7!!