I'd be interested in getting peoples' take on the recent Freakonomics podcast, "Is Learning a Foreign Language Really Worth It?" http://freakonomics.com/2014/03/06/is-learning-a-foreign-language-really-worth-it-a-new-freakonomics-radio-podcast/

The Economist reviewed the podcast here, 

http://www.economist.com/blogs/prospero/2014/03/language-study.

1) The premium for knowing another language ends up being pretty significant over one's life (especially for languages which few people in your country know, but for which there is a big demand like German);

2) Foreign languages command more value in export-driven in economies; and

3) There are always opportunity costs when you study a subject - literature, art, history - and yet the authors don't analyze the ROI of these subjects.