A claim made here about Duolingo and translating Wikipedia:
http://www.bbc.co.uk/news/magazine-18367017
"With 100,000 active users, von Ahn says Duolingo could translate Wikipedia from English into Spanish in five weeks. With one million users, it would take about 80 hours."
Our article on Duolingo is here:
http://en.wikipedia.org/wiki/Duolingo
Carcharoth