Matt, that's the thing though:
Most of the sword-training in Japan is Kendo. The defining organization for all swordsmanship in Japan should still be the Zen Nihon Kendo Renmei, the All Japan Kendo Federation - unless UFOs have taken over Japan in my absence.
The "Nikkenren" (for short) to the best of my knowledge recognizes iaijutsu and has forms for it, but I've never heard of it describe Iaido as one of its arts, and never a belt classification.
Iaijutsu as I have understood it is a form for drawing, striking, and returning the blade to the saya, all in the same motion. I know back home Yagyu Shingakeryu (based I think still in Sangenjaya, Tokyo, about 15 min away from my dad's house) still does traditional swordwork, but such places I thought fall under the name of Kenjuku, or "sword academies."
Not to say that it doesn't exist, but you have to understand that in Japanese the difference between ~jutsu ('method')and ~do ('way', though actually untranslatable) is a hair's breadth. Any recognizable body of combat techniques automatically earns the ~jutsu suffix, i.e. ninjutsu. It earns the ~do suffix, when it acquires a perception of artistry (which can be downright prissy at times.) An absolute prerequisite for this is the creation of forms, and it is around these kata that the various schools and branches, the ryuha revolve. Everything else is pretty much exclusionary, never mind tinkering with the forms. That sort of thing gets you thrown out quick back home.
At any rate, a few calls back home sufficed to put things into perspective ... yes there is Iaido, just that I'd never really focused on it (the Kendo aegis under the Nikkenren in Japan is HUGE) and certainly never heard of a belt classification. To be honest, I don't deal with Kendo anyways. People learning different arts in Japan tend not to mix. When I was in high school the Kendo people wouldn't talk to the Judo people and vice versa. I found it hilarious.
Sorry about the mixup.