The ESRB has listed a rating for an unannounced Atlus game called My World, My Way. While this could be anything, Siliconera's Spencer conjectures that this is a localized version of Global A's Sekai wa Atashi de Mawatteru (The World Revolves around Me), an interesting RPG from earlier this year in which the player controls a "selfish princess" who alters the landscape in order to complete objectives.
Supporting the belief that this is the mystery game is the fact that just released another Global A DS game: Master of the Monster Lair was published in Japan by that company. We'd be happy if this turned out to be true, because we thought Sekai wa Atashi de Mawatteru looked really interesting, and, of course, having Atlus attached would only make it seem more so.
While we're on the subject of ESRB ratings, a few more DS titles caught our eye as interesting: Atari's The Chase: Felix Meets Felicity, which we totally don't know anything about, and the very cool My English Coach para hispanoparlantes.