According to this GamePlayer story, server space in LittleBigPlanet will be limited, so you won’t be able to just keep uploading levels from the blue-sky PS3 platformer to your heart’s content.
All is not lost, however. Those that create more popular levels will be allocated more space, apparently, meaning the more creative in the audience will be given room to shine.
There’s no source for this, but the Media Molecule chaps are at Develop today. We’ll try to grab them later.