Well, I do have the WiiWare version (haven't beaten it yet though, last levels are a pain, lol) though I heard somewhere that the PC version has some sort of level creator. Is that true? I've been thinking if I should get it or not...did 2D Boy say anything about an update for the WiiWare version yet?

Nnnnnno. Not really. But I understand the confusion.

2D Boy never released their level creator because they said it's far too convoluted and user unfriendly. However, they HAVE released certain tools which have helped members of their community (ie: the forum goers at 2dboy.com) put together level editors (and level packs, obviously) of their own.

Last I heard (when I was hanging around their forums), 2D Boy has no intention of ever releasing an official editor, but they do encourage amateur development passively. So yeah, those tools do exist, but they're not official, and I can't vouch for their usability. If you want to poke around their forums though, I'm sure somebody there will be happy to answer your questions.

If you DO get into that sort of thing, I'd be very interested in hearing your experiences!

Oh...well nevermind then, I might look into those tools eventually but I dunno, I'm not good with advanced tools and all that anyway, lol.

...checks 2D Boy's site
Um, I was gonna look into the tools and stuff, but on their homepage they had some news article of some mysterious goo-like...thing....lol. OMG IT'S AN ALIEN! lol

Ive seen a few (but not played) user created levels and there are some pretty cool looking ones.

I remember there was a christmas themed one where you had to build a goo tower up a chimney to reach the pipe.

Edit: here is a link to the xmas level and a pretty good site for user created goo goodness