Soul Sacrifice will be released on April 30th in North America.
Furthermore, the game will be released in Japan on March 7th. Game Spot states that the following will be exclusive items if you reserve the game:
Pack of in-game content that includes two costumes, three magic items, a Spirits’ Flamepike, a Spirits’ Blightstone, and a Spirits’ Fulgurwood.
In addition, those who preorder Soul Sacrifice will receive the Japanese voice-over pack for free. This will be sold separately, but the only way to get it at launch is by reserving the game.