You pick up to 3 characters (KOF style team battles) and an item, which provides you an effect when used and access to a unique super. Or you can pick less characters but more items. The forward dash clashes with non-low moves which turns it into a parry of sort. IIRC you can spend meter to call your team mates as assists. Lots of cool shit.
Shin Koihime Musou Arcade Edition
It's out now on PC, and soon on PS3.
This game is extremely similar to SF2, but with assists, EX moves, and fatal counters.
I made a tutorial long ago:
Out on JP PS3 but coming very soon to America with a very cheap price tag.
This game plays like a cross between CVS2 and Capcom Fighting Jam. Each character has its own system of rules to play within, but the assists can provide additional groove like features. Like for example one of the singer assist activates a genei jin for your character, and the other activates a seiei enbu. The emotion system heavily rewards offensive play, functioning as both a guard break system and gives bonuses for the attacker.