Link: http://www.ps3fanboy.com/2008/09/10/littlebigplanet-takes-a-big-amount-of-space-up-to-40gb/
LittleBigPlanet takes a big amount of space: up to 40GB on Blu-ray
The tutorial content will be extensive in LittleBigPlanet. "We're filling the Blu-ray up with is tutorials, and a lot of video stuff showing exactly how it's done, it's narrated by Stephen Fry and so on. It's really useful that thanks to Blu-ray we haven't needed to worry about file size, it's never crossed my mind." However, this doesn't mean the game will be bloated when sharing levels and creations on the web: "The game itself and the levels you produce are relatively compact."