A button push flips the planet's surface to levels created by the LittleBigPlanet community, while My Moon is the gateway to your own creations, whether you've chosen to publish them to other players or not. You don't need to publish a level/room/art space/whatever in order to share it - you can invite anyone you like inside.
We're shown a level called The Plains, with an African savannah theme and a structure that's a straight, competitive race to the finish, picking up as many bubbles for points as you can along the way. There are giraffes whose necks raise the sackboys to higher levels when they stand on their heads, tip-dispensing monkeys, and a dangerous stampede of wheeled buffalo. Other levels, like the country garden level from the game's GDC unveiling last year, are more co-operative in design, with sections where players must help each other to surmount the obstacles. As an example of a different scale and style of level, we're shown a simple rope-skipping survival mini-game for two players.
One of the prinicpal rewards for playing through LittleBigPlanet's offline levels is to unlock new items to add to the "Pop-It" creation menu that appears as a glowing thought bubble, tethered to your sackboy. These include materials (physical properties), tools (pistons, pivots and so on), stickers (textures and decoration) and sackboy costumes. The latter will be many people's route into content creation with LittleBigPlanet; even if you're daunted by the idea of building anything, you won't be able to resist the urge to dress up your avatar. (We chose mirror shades, collar and tie, and pink, floral, Laura Ashley skin, since you ask.)
Puppeteering is another itch it's impossible not to scratch. Tilting the sackboy's head or hips around with the Sixaxis' motion sensors, waving its arms in the air with the right stick, emoting with the d-pad (you click through three levels of sad, happy, angry and scared)... it's the most flexible, immediate and instinctive form of self-expression we've ever seen in an avatar-based game, and it's got immense charm and entertainment value in itself.
We don't get as far as trying to build anything in-game, but can report that Pop-It is attractive, logical, simple and extremely fast. It speaks volumes that Media Molecule is using the game itself to make the game - although there are currently several layers of complexity to the editor that will be left out of the final release. A lot will depend on how easy it really is to utilise tools like pivots, pistons and switches to create mechanical devices and simple AI; you can clearly do a lot with a handful basic rules, but how intuitive will it be to work out which rule you need? Nonetheless, some of the simpler presentational tools are easy to imagine using to great effect, such as mouths that dispense text messages, and little ghetto blasters that, when passed, can change or build any musical track from Media Molecule's library.
Fundamentally, however, platform games have to be about the joy of motion above everything else, and that includes dressing-up, playacting and world-building. And this, happily, looks like it could be LittleBigPlanet's greatest strength. It's not as precise or involved as a Mario, but using the most basic controls imaginable it conjures up a joyful, elastic, tactile momentum that brings an instant smile to the face, and works perfectly with the impressively consistent and fun physics. There's an immediate and deep-seated pleasure to be had from the simplest interactions in LittleBigPlanet's world - something that, along with its quirky, homespun looks, reminds us very strongly of Katamari Damacy.
At times over the last year, LittleBigPlanet has sounded too clever for its own good - too clever, at any rate, to be the PS3 smash hit Sony wants it to be. Don't be misled; it's one of the simplest and most appealing propositions we've ever sat down in front of. It's 21st century Lego.
It's going to be fascinating to watch LittleBigPlanet go head to head with that other poster-boy for the community-creation age, Spore, when they both release this September. Spore might be more successful by virtue of its platform and pedigree, but at the moment, the PS3 game looks the more coherent, consistent, easy to grasp, rewarding and just plain lovable. It may not be the biggest PS3 release this year, but one thing's for sure, it's absolutely the most important.