You'll be just fine. As someone who has employed a number of translators in my professional career, the biggest issue is trust. Translation is scary because it's one thing you have no ability to self-validate. While duolingo is incredibly smart, they're going to have to go a LONG ways towards building trust that what they're producing is truly what my app, brand, whatever wants to convey.
Nah, it's not just Duolingo. Google is making frightening inroads where it counts - they just won a hugemongous contract from the WIPO that a lot of people were hoping for (I was asked to be part of the team by at least four agencies placing bids). Statistical methods work pretty well for a lot of applications, and patents are probably one of those applications.
Actually, I think Duolingo is going to help the translation market for a while - anything that brings people closer together between languages is going to encourage more people to need quality translation - but they intend to train massive numbers of people to do what I do for a living. And once that system is in place and honed on Wikipedia, they'd be insane not to employ it for placing contract translations. The notion of employing multiple human translators and combining their input to produce a better overall output is fantastic! It really is! The only reason nobody's done it yet is the expense of paying for the translation multiple times - and that's just about to go away.
No, seriously. I've been predicting five to ten years for the limit for the industry already. This just tells me how right I am: things are going to start getting freaky weird for me.
It's about damn time, too. I'm bored sick with translation. I want to get back into programming anyway. If I can figure out how to combine them, I'm going to be a happy man.
That's going to take awhile.