Square Enix has announced that The World Ends With You will be released in North America on April 22, 2008. If you are still unsure what this game is about, here's a brief description taken from the official press release:
"The story begins as Neku Sakuraba, an unsociable 15-year-old boy, unexpectedly wakes up in the Shibuya shopping district of Tokyo, Japan. While trying to piece together his rude awakening, he receives a strange text message warning him that he will cease to exist unless he accomplishes a certain mission. Although he barely has time to grasp what is happening to him, he commences his assigned task in the mysterious streets of Shibuya."