Well, here I am at last...
Although I've heard about this website from various user-created levels on LittleBigPlanet (including the Logic Pack, which I found to be a nice, informative series of levels on how to create simple logic mechanisms before LittleBigPlanet 2 came along), I just decided to join soon after my sister got LittleBigPlanet 2 (which is a great game by the way, though I'd bet that you guys already knew that ;) ). I hope to be able to contribute to this already fantastic game by suggesting some ways to improve upon it even more (such as allowing sackbots, especially those controlled by a player character, to swim in water without short-circuiting in the process, or use jetpacks or grappling hooks).
Although I can't remember how long ago it was when I 1st got LittleBigPlanet, I do remember that I had it for more than a whole year (since before the Pirates of the Caribbean pack came out). While I did create and publish a few levels on LittleBigPlanet, most of them were originally meant to be part of some larger non-linear adventure (about as non-linear as Super Mario 64 or Super Mario Galaxy) in which you would need to collect stickers to progress throughout the adventure. However, it seems to me that planning out and creating just one of these levels took me several days, sometimes a week or 2, so I've since decided to cancel the project, though I'm currently thinking about creating a platform-adventure campaign (sometimes referred to as Metroidvania or Castleroid, since both the Metroid series and many of the games within the Castlevania series, such as Symphony of the Night or Dawn of Sorrow, belong within this sub-genre of platforming games) since I think that it shouldn't take nearly as long to create as that non-linear campaign that I had originally planned to create. Besides, I think that with the new tools that are available for LittleBigPlanet 2, such as the sackbots, controllinators, compact logic mechanisms, and level links to name a few, such a project would be very much possible.
Generally, I'm a big fan of platforming games in general, from the easier games such as in the Kirby series, to the harder games such as the Donkey Kong Country games. Likewise, in LittleBigPlanet, I like to make platforming levels, sometimes ones that are pretty challenging. Sometimes, I'll incorporate gameplay that's normally found in side-scrolling shoot-em-up games (like Gradius or Raiden) or run-and-gun platforming games (such as Contra or Metal Slug). Occasionally, I'll incorporate so-called "bullet hell" gameplay (in which the player must dodge many projectiles that come at him/her simultaneously), though if I do, then I'll try to keep the gameplay not too difficult (usually by making the projectiles move slowly so that players would have enough time to react).