Duolingo does Japanese now

Actually, Duolingo has been doing Japanese (on the phone app versions at least) for the past month or so... I decided to give it a go, see how it might fit in to my regular Japanese-learning regimen, that sort of thing.  My verdict:  it's... mostly OK, but I wouldn't recommend it as a primary source for learning the language.

The most obvious problem with this software is that it explains nothing.  At least from what I've seen so far, everything is taught through example, which is fine for most things, like basic nouns, verbs, and sentence structure, but doesn't necessarily serve well for "set phrases" that are roughly translated for the use they serve, without noting the actual translation that's just as valid... a good example would be いただきます, which I think gets translated as something like "let's eat" instead of "I (humbly) receive".  Of course, that may be the same sort of glossing over you see in introductory-level courses anyways, and at least this program actually teaches you the sound associated with individual characters (unlike some programs I've seen)... but then they introduce kanji into the mix early, without any warning that, oh by the way, these characters have multiple pronunciations depending, which isn't really helpful for students long-term, I wouldn't think.

The biggest problem I have with this program, however, is that sometimes it's Japanese is just wrong (from what I think I've learned so far).  I can understand why that might be, based on how I think they pursued their translation engine as a programmer, but that's doesn't excuse mis-teaching their users.  There are two main examples I can think of so far... first, instead of ではありません, I've seen them use じゃないです, which at least parses out alright, but strikes me as the sort of thing that might make a native speaker go "well, they're a foreigner, and they're trying, so it's OK".  A better example might be Duolingo's use of ほしい when you're saying someone else wants something (which you're basically not qualified to say with certainty, the correct version being ほしがる, which is more like they look like/seem like they want that something).

Those complaints aside, it is a good tool for drilling with and expanding your vocabulary, so at the price of free (with ads), it's worth using... but if you want to start learning Japanese, I would still suggest starting with Human Japanese, and maybe use Duolingo alongside... and listen to the dedicated Japanese program if you run into any conflicts between the two.