<span style="font-size:24px;" class="blue">Learning is a game.</span>
look like they ought to be links to describing the features (they're blue!) and so sent me needlessly changing NoScript settings, to no avail. If this is just unimplemented, then OK, but otherwise you should change the colour scheme before leaving beta, or your users will be wasting precious seconds on the front page. (Apologies if you already knew!)
Human Japanese - basically an interactive textbook, with audio clips and interactive quizzes. Probably the best of the bunch.
Pocket Japanese - based on several series of podcasts, for different skill levels. Each lesson has a ~10min podcast, sentence by sentence breakdown, ~1-4min review track, vocabulary flashcards, and written grammar lesson. Interface can be a bit annoying, but the content and features are good.
iKana - for learning Hiragana and Katakana
AccelaStudy Japanese - for pure vocabulary cramming, very polished.
To the Lingt team - if an iPhone app isn't already on your roadmap, it definitely should be. It's a ridiculously convenient way to learn a language.
I wonder if there are as many resources for korean.