I agree that Japanese/日本語 isn't primarily used for study - but that's okay.
I still think it would fit better in "Studies" (should there be such a category,
which I am still proposing, since there are some boards who would fit better in
that category than they do in any of the existing or other proposed ones).
Also, there aren't any other language boards and it's not likely that they are
going to be introduced anytime soon.
So instead of pregrouping boards into categories that don't make much sense yet,
I believe it makes more sense to organize the boards as they exist now.

Rehash of my "vision":

Rules

• General Talk

General
News
Politics
DQN

• 4-ch Projects

Requests/Feedback
#4-ch@ZiRC
4-ch wiki
Team 4-ch F@H
2ch Portal
Donate

• Otaku Hobbies (or just plain "Hobbies")

Anime
Manga
Games

• Culture

Food
Film & TV
Music
Net Culture
AA Bar

• Study

Science
Technology
Programming
Japanese/日本語