The thing I found interesting in this article is that switching contexts actually increases the amount you can learn. From what I understand, this would mean studying grammar, character reading/production and vocabulary at the same time would be beneficial. I never quite understood why this was the case before, even though people have told me it is so.
My only concern with Anki is whether it still uses some variant of the SM-2 algorithm and whether or not the people implementing the software are doing more than just polishing interfaces, etc. and actively work on improving the learning algorithm. Looking at the history, SuperMemo on SM-11 http://www.supermemo.com/english/algsm11.htm and Wozniak claims that there is a substantial evidence that this algorithm increases the speed of your learning.
There's actually a Wired article about the author of the software http://www.wired.com/medtech/health/magazine/16-05/ff_woznia... Completely eccentric and totally devoted to using the thing. I mean he doesn't even decide when he responds to his own mail, Supermemo will "schedule" it for him. I believe the latest version supports something called "incremental reading" which Wozniak claims is better than the usual order we read things. You read till you get bored/tired and them move on and it'll keep track of where you were, etc.