A promotional clip for an upcoming Idolmaster event appears to be teasing a new title announcement for later this month. In the video, which you can view here, Hibiki begins to say something about a new title being announced at the end of March, before she's cut off by her fellow virtual idols.
The main focus of the clip is Idolmaster's appearance at the Nico Nico Chokaigi event, which will be held on April 28 and 29 at Makuhari Messe (for details on the event see the official site). Namco Bandai will host a live Idolmaster concert on the first day of the event.
The Idolmaster franchise includes more than just games, of course. It's possible that this could be anime related.
Before the end of March, we should also be getting an Idolmaster mobile announcement, as detailed last week.