I pre-ordered World of Goo some time ago and then said "hell yes, I'd love to playtest!". A couple days ago, I actually got my copy of the beta version and I have to say two things, the first of which is: "Damn!"

Secondly, it is a seriously fun puzzle game, with interesting sound effects and creative solutions. The trailer really doesn't do it justice, but I'm seriously looking forward to having the full version of it instead of just the first chapter.