Machine translators are learning fast. And they're not only translating text better, the past few months have given them the ability to translate both audio and video on the fly (read past the break for the second demo video). For the common man, reading a menu in Japanese or bargaining for a mat in Arabic is becoming an obsolete skill, a 20th century relic. Why bother with all the time and effort, when you can just delegate the job for the assistant in your pocket, more commonly known as a cell phone?
However, I don't think this means people should stop caring about teaching languages, or that translators should worry about their jobs. Conversely, if the amount of language students does decrease, expert-level skills might even rise in value. The data for the translation systems has to come from somewhere, and the need for quality translations will not go away. It'll take more than Google to translate a novel or even subtitle a movie. Like on every other area, machines are tackling the boring jobs better and better, while humans can enjoy the more interesting and specialized avenues of work. And while technology is punching holes in language barriers, cultural understanding becomes increasingly important.
Learning common courtesies in another language will still be worthwhile, learning how to act in social situations and obeying local laws and traditions while travelling will become more important than ever. Getting deeply engrossed in an another culture via language will still be an enlightening experience worth having. And exploring other cultures more superficially continues getting easier, thanks to the Internet. Besides the Google Translate demo on the top of the post, be sure to watch this amazing Spanish-English demo from an American startup, too: