Delivery Cupid on Amazon. It stood out to me because Delivery Cupid has already come out in English in North America-- it was one of the few BL titles released by Broccoli Books USA before the company shut down. So I clicked the listing for more details and discovered that Delivery Cupid appeared on the Kindle on March 24th, and its publisher is listed as Libre Publishing Co. Ltd-- also known as Libre Shuppan, Japan's biggest BL publisher. It is, as far as I can tell, the only Libre listing on Amazon.
So there you have it: a Japanese publisher reaching out to the North American audience without the benefit of a middleman. Or mostly-- obviously Libre had the bonus of having a fully localized copy of the book already in their hands thanks to Broccoli. On the other hand, mangaka Aya Fujii apparently hired her own translator for her Peach Boy series. Still, though, I believe this is the first Japanese publisher I've heard of publishing manga on the Kindle in English.
It's not exactly unheard of for Japanese publishers to consider alternatives to the licensing route; I recall a particular program that was designed around the idea that its users would translate the manga, and could then sell the translations via the same program, with a portion of the profits going back to the original publisher. But none of the major pubs seemed very interested in it, and the program dwindled.
But here we are, with a well-known Japanese publisher dipping its toes directly into the waters of North American manga readers.
What do you think? Could a day come in the future when Japanese publishers retain their own translators and release titles digitally, rather than licensing them out? Anime companies are half-doing it via Crunchyroll, which generally helps them out on the translation front but which does not provide physical copies.
More importantly, would you be interested in getting manga in this manner? You don't have to have a Kindle to read a Kindle book, after all; Amazon released free software for reading them. Would you try it?