Pretty slick. If I remembered any Japanese from my early High School classes, I'd be impressed. At the moment though, I'm simply perplexed
. Um, so, are there plans for a Super-Beginner mode? So you look at a bunch of katakana and hirigana, but the english pops up too? Then, after a little practice you enter the area with no translation? Be kind of nice.
EDIT: Or have an option to flash up an english translation once the balloon plummets out of view. That'd be nice.
As for marketing... have you tried aiming at educational institutions? Or! Anime sites? I'm sure there's a large group of people who would love to be able to read the original Japanese, if only they had a nice learning tool. And this is rather nice.
Good luck with this! Noble cause.