Didn't read the full article, but tried Skitter because just to check out the free trial.
Wow... I actually think this is pretty good.
I have used kanji box and anki, and while I agree those are good programs too, with out any delay this one lets you study right into the nihongo matome series which I am using to study for N2.
while I think writting on the screen is kind of a gimmic that doesn't usually work very well, this is worth a go! the way it corrects your patterns in the kanji is really fluid and I found I was actually remembering the strokes because it's testing me again in the perfect amount of time. I'm impressed here!
It tests you in many different ways (reading, meaning, kanji) so it doesn't get boring or repetitive which I liked a lot. I also like how you can track your learning really easily.
I also downloaded and tested the app for iphone. wow.. I much prefer the online PC study version.
**It works very similar, but for some reason the app version has a stupid corny Japanese theme to it that I personally hate and find pretty ugly haha. The kanji and words are presented in a slightly different font to a text book or computer to match the stupid theme which irriatates me.
I really don't like the app for this, feels cheap. If I was looking for JUST an app to study with I would get something without a monthly subscription. However for those who also use a computer a lot to study, its probably worth signing up for the trial and giving it a go!