Absolutely fantastic! BUT...
Great, very well made, you can see how it went into much thought. My only request is: expanding the number of languages. Out the boundaries of Romance languages. Maybe Arabic (Classical Arabic, Arabic itself has a lot of dialects) or Korean / Mandarin or even - learn Latin! Meanwhile, I have only good words on the interface, design, and implementation. Duolingo is wonderful.
Hi! Yes, we do get lots of requests for more languages and have mentioned more recently that we'll be making it possible for the community to add languages soon. This is a project we look forward to sharing more about in the upcoming weeks. :)
Woohoo! Giggles.... "weeks" I just noticed you said "weeks". Everything else I'd heard was in the distant, nebulous future. Wow. now, I have something to look forward to. I know I shouldn't get too excited because this might just mean we will get an announcement stating new languages will be added in the upcoming year or so, but this is almost a firm date. AWESOME NEWS.
And, sadly, there's a good chance that Kristenmc's comment will get buried because people are down voting this discussion.
There are hundreds, but they usually just get downvoted in a few hours so they are moved down the board and out of sight.
"The other day we found a quarter under the couch. I think that's the entirety of our revenue so far." - Luis von Ahn, May 2013