Studied abroad twice in college, and have done a pretty good job of keeping my language ability on life support via weekly face to face language exchanges with native speakers. So I think this idea makes a lot of sense. I wouldn't say they helped me learn anything, but it has helped me to keep from forgetting.

It seems like this kind of system has a couple of markets. I think the reason a lot of Spanish speakers are using it, is because they may already have book learned the basics of English, but lack the day to day interaction. So that's one segment. It seems like this site is a sweet spot for them.

But another segment probably not as well served would be people who are completely new to a language. Most language partners won't have the skill to introduce someone who has no background in it. So I think the uptake for these kinds of language learners would be low.

One thing that would be really awesome is to consider integrating some kind of learning curriculum. But the trick is if you had to supply curriculum for every language, that won't scale well at all. Instead, consider the barefoot language learning school of thought:

http://www.amazon.com/Language-Acquisition-Made-Practical-Le...

This book is out of print, but it's an amazing guide to learning any language without a textbook provided you have a language partner.

Graphical dictionaries for language learners would also be super helpful:

http://www.lexicarry.com/

Also, for more advance learners who are already able to carry out basic conversations, topic suggestions would be super helpful to keep the chat flowing. You can only talk about your family for so long...

I looked to sign up but none of my languages are supported yet, otherwise looks promising.