I hope it's not going to happen. The fact that the people in the world speak so many languages makes the Earth so diversified and beautiful. Yes, sure there are languages acknowledged to be more popular and and really useful in international relationships, e.g. English, German or even Chinese. I myself am not a native English speaker, but I'm doing my best to learn as much as i can because i know it's gonna be very useful someday, and it already is, cuz I'm writing this argument, aren't I?

So, yes, it would be great if everyone understood everyone without the need of translation, but it would suppose melting all the other languages into a new one and then everyone would lose a huge piece of his/her ethnicity, culture and the world that's so colorful now would become simply black and white. It's just not worth it. :)