JeuxVideo says it's to reveal a "major PS3 exclusive" in a live video show during the evening of May 2.
We've no idea what the game is, but speculation based on this Sony job ad (via SixthAxis) hints that it may be some sort of MMO based in the LittleBigPlanet universe.
Sony scheduled its E3 press conferenceyesterday, but it's clearly got some big news it just can't save until June. Last week it began teasing a PlayStation reveal scheduled for this Thursday, with the rumour mill suggesting it's a new God of War game.The platform holder also said last Friday that the currently Japan-only red PS3 will launch in the UK on May 4.

http://www.computerandvideogames.com...red-for-may-2/