Soultaker has written to let me know that the World of Goo translation wiki will be closing soon. With the game out for more than four years, and the last major translations updated in 2010, I think one can say it has fulfilled its purpose!
I think it would be good if someone would like to take the full translated plain-text XML and package it into a goomod for posterity, perhaps doing a quick check for any overlooked spam first. Drop a note down below if you're doing this.
No sooner said than done, Mygod has taken all the final user translations from the wiki and packaged them up for future generations to enjoy.