Hold on. Doesn't this mean that Astro Boy is not manga? Since most of it was made before the official manga style even existed?
This entire argument makes no sense. Not picking a bone with Apples still, I mean in a more general sense. This argument really has come up way too many times.
Art is constantly evolving. The modern 'moe' style of manga and anime looks almost nothing like alot of work from the eighties.
My point is, Manga is a really, really vague word.
So if your art is vaguely Manga inspired, then...
Well, you're good. :/
Art is supposed to evolve. You are supposed to use your own style, not just unthinkingly ape somebody else's.
So having somebody tell you what is and isn't allowed doesn't really serve a purpose at all.
You know, this reminds me of an artist interview I read awhile back in a magazine. Her style, to me, clearly looked like manga-style but you know what she classed her art as? "Low-brow street art". No mention of manga or anime at all.* I think it all depends on how the artist see themselves, their art, and how they would like to define it. At the end of the day, whatever the artist wants to define their art - fine. I'm down with that. I'll still think of their work as either falling in one style or another though with my own set of criteria.
Btw, here's some of her work. Camilla D'Errico:
* Though her DA says she grew up with cartoons, comics, and manga.
Anyways, I think I feel your frustration apples though for my part, I'm more personally interested in just getting people to sign up and contribute rather than having people post mainly manga-style art work. My thought is that if you can get an increase of members, then generally, postings of art specifically what this site is aiming for will follow. New members interested in this art style => more postings and questions about manga => more manga art.
With that said, I am not opposed to people posting other styles of art. Manga does range in style from realistic to super deformed and cartoony after all. If folks who've come here still maintain at least some of their manga-style roots, I'd be happy to at least been a factor during that artist's "period" of art.