What is the "Preview" version? And why does this need to be shared? And are you spam (because with the amount of spam on these forums nowadays, it's difficult to tell what's real or not.

From 2dboy
World of Goo Chapter 1 Preview Download Bot
If you pre-ordered World of Goo but never got the instructions for downloading your copy (may have been sorted into spam folders we hear…), you can download it here with your Magic Key: World of Goo: Chapter 1 Preview downloader. If you never got your Magic Key, let us know here!