Just because LittleBigPlanet 3 was only shown on the PlayStation4 back at E3, that doesn’t mean that is the only version of the game that we are going to see. Although it wasn’t announced at the show, a PlayStation 3 version of the game has since been confirmed by the LBP community manager, Steven Isbell.
A bunch of fans flooded the community forums and staff with questions regarding a potential second version of the game and Isbell let it be known on his personal Twitter that it would in fact be launching on Sony’s older console. The details are still forthcoming as to what, if any, content differences will exist between the two versions (or perhaps if it will support Cross-Buy).