You wouldn't know it from looking at it, but that video up there is actually off-screen handicam footage of a 3DS' screen. Right? As it turns out, the debut trailer for Shin Megami Tensei IV was tucked away inside the 3DS re-release of Devil Summoner: Soul Hackers, which doesn't actually come out in Japan for a couple more days.
Things look bleak in SMTIV, what with all the destruction and desolation and chilly-lookin' weather and everything, but gameplay and/or story details remain scarce on account of our inability to speak or read Japanese. At any rate, we do at least know that the game will be out sometime next year.