Just about everyone who owns a PlayStation 3 and a human heart has purchased LittleBigPlanet, so you know you're going to play it on your PlayStation Portable when it comes out. Here's another reason to pick it up: It looks like the PSP version of this game will support "professional" expansion levels along with fan-made content, just like its big brother on the PS3 does.
Game blog SiliconEra spotted a menu screen on the coming-soon PSP version of the game reading "Story Levels", "Downloaded Levels" and "Purchased Levels," so get out your credit card, son. Whether the purchasable levels will be available in the final build of the game remains to be fully verified, but it sure looks that way.
Buyable levels/accessories and costumes are already supported in the PlayStation 3 version of LittleBigPlanet, including the Metal Gear Solid level pack and the Festive Pack released around Christmas, so it's no shocker that you'll be able to buy new platforms to jump off when the game his the PlayStation Portable. No word on a release date yet, by the way.