I think the first thread I made's giving out a 404 error because the wiki page it was linked to got deleted, so I'm making this one for anyone who hasn't seen it yet.
Atlus has announced Persona 4: Dancing All Night, a “sound action” game for PS Vita in development at Hatsune Miku developer Dingo for a fall 2014 release in Japan.
Persona 4 characters like Yu Narukami and Rise, as well as new junior idol character Kanami Mashita, are confirmed to appear as players “Battle Dance” against shadows in a mysterious world known as the “Mayonaka Stage.”
So I just found out that the game will have a story to it and that it sounds pretty ridiculous.
I don't like Yu's dancing; it looks awkward as hell. The announcer in that video is also... weird. I'm interested in this, though, because it's Persona, I like rhythm games and Persona has good music.