LittleBigPlanet community manager Sam_Protagonist, who claimed the development team had "no plans to introduce" image importing into the game. Clearly, this "work in progress" (as it's called), which appeared in Media Molecules Flickr stream yesterday, shows that the team is developing an "Image Import Tool" that pulls images from the PlayStation 3 hard drive and sticks 'em to players' creations. Indeed, in his denial, Sam_Protagonist did admit that importing is "very much technically viable."
Still, as Sam implied, there are obvious copyright and balls-on-the-walls issues that complicate the introduction of an image-importing tool. Until those are resolved, consider this update for internal use only.