Yeah, I think if it's this major, with a countdown and everything, it's not another mobile game. [they have like... 3 now, right?]
I'm personally hoping for some more of the DS crew, maybe a 3DS spinoff? They have been getting a lot of attention from Namco lately: g4u appearances, some cameos in the anime, and dlc. Whereas... like a year ago all we had heard from the DS series was a mention of Cineria in the rankings.
I also heard something about a big anime announcement!! in April, although that was from a friend.
Although... I'm not expecting much. It's probably a reveal of who's voicing who in the Cinderella Girl cds.