I really can't tell the difference between eromanga and doujin. Apparently the difference is "usage of original characters and the generally poor paper quality." The hell?
Doujin(shi) means it's self-published by the artist or a circle of artists. It can be ero or non-ero. I believe there are more non-ero doujinshi releases but only the ero ones tend to get scanned (big surprise).
Eromanga can technically be doujinshi or commercial manga (i.e. magazines, tankoubons, books). If it's meant to not include doujinshi then eromanga isn't really the right term to use.
But I don't really see the distinction as being useful anyway. There's a lot of crappy, awfully generic commercial manga sold just as there are crappy doujinshi. And so if eromanga is meant as a "this isn't a crappy doujinshi" tag then it's doubly the wrong term. Even more so because quality is subjective anyway.
I tend to mark obvious manga scans as manga or eromanga only if they seem to be commercially published, and as doujin only if they seem to be parodying an established series (which I assume would not be allowed in a commercial venture, and so therefore marks a work as being doujinshi). I'm pretty sure that on the English-speaking internet, this corresponds pretty well to the lingo in use - people often tend to correlate the word "doujin" with "fan works for established series", though this is not literally correct.
Mostly, though, I just tag them as monochrome and leave it at that.
Yes rly. 1) We discussed this recently when someone was uploading chapters of some manga I can't recall at the moment, 2) as your link shows, albert hasn't really done it in almost half a year, and just going to page 2 is nearly a year ago 3) we have repeatedly been discouraging full manga/doujin uploads in threads and comments for some time now. Fairly certain I've seen you discourage it too.
Edit: Oh, I think I know where the discrepancy is. I have a specific definition in mind of "commercially released manga" here. Danbooru isn't the place for, say, uploading the latest Japanese Bleach chapter (scanslated or raw). Danbooru isn't the place for uploading scans of Yen Press' English release of Hidamari Sketch. Basically, think forum #3117. Just about everyone gave him an emphatic no regarding the Elfen Lied stuff, you included. Danbooru's not a scanslation hosting site.
When it comes to less obvious things like naruko_hanaharu's latest short hentai one-shots that presumably ran in some commercial magazine of some sort, I have less of an opinion on the matter, although I'm still not going to approve it in the queue.
As for uploading single pages, I'd apply the same criteria as with hentai CGs - we don't want the whole thing, so it has to stand alone, and they rarely do.
