I just finished World of Goo, and dammit, it's fantastic. It's crazy that a game this good can be produced by just two people.
You should play it right now. You've got no excuse: it's available for Linux, for Mac OS and for the Wii. The Windows distribution channels are numerous (including Steam), and there's absolutely no regional price differences (not the case for many recent releases: I'm looking at you Farcry 2 and Fallout 3).
If you don't know whether you'll like it, well, screw you. You should be able to take my word for it. Of course, I'm not the only person who thinks it's great (that score is equal with Half-Life 2). And there's a generous, substantial (and free) demo that should convince you of the game's merits. You have nothing to lose but your ignorance.