The Playstation Blog announced that they will release the demo for Soul Sacrifice today on the Playstation Network. The demo is fully functional and includes the first chapter in its entirety. And that's not all! Not only does the demo have the entire first chapter of the game, but it has local and ad-hoc multiplayer as well as letting you save your progress to transfer into the full game!
You can read what Keiji Inafune said about the demo after the break: