Late story but one that should be covered. Persona 4 was unveiled by Japanese magazines and at the time of the reveal, the game was heading straight for a 10th July 2008 release in Japan - on the Playstation 2. The game is separate (apart from recurring themes) from the critically acclaimed Persona 3 in that the setting will be much more rural and is more of a mystery thriller with fog replacing the full moon in the game. A large DVD trailer was given out in Famitsu and various videos have sneaked their way onto the Internet. The 2 trailers making up the DVD are embedded below with the much smaller introduction movie below that.
No word on whether this will make it to Europe though the US should get it easily.