I just saw this, so I'm posting my comments.
I'm not sure everyone will agree, but it is what I think.
The most influencial author?
There is only one thought that comes to mind in that category, Ichinohei Hitomi.
The reason why?
She influences us in so many small, almost unnoticable ways.
How many people thought about Ukyo's legal position before A Son's Duty?
How many people knew about the tea ceromony and what it involved?
In fact, with the publishing of "An Alternate History of Ranma 1/2", she took us into a world that we never saw before, and then we had to reread the first chapter of Ranma to see everything we missed, but was in her writings.
She's also able to flesh out the characters in ways that most of us would never think of.
Did you ever think of the financial situation at the Dojo before Hitomi?
How about Kasumi, and how her actions changed from the first Manga issue to the later ones?
Ranma's feelings, or Akanes, or Ukyous?
How about all the pitfalls of honour that the Ranma series has in it, and how that is important to the story?
And then there is the help that she has given over the years.
I don't know about you, but whenever she writes anything, a lot of us start to think.
>From physics, metalurgy, questions of honour, recipies, feelings, and others, Hitomi has changed the face of how and why we write. Many of us even try our hardest to duplicate her writing style.
Elements of her writing style, her ideas, her comments show up in about 7 out of ten fictions, even if we don't realize it.
Recently, (as everyone can tell you) I've been trying to go through the FFML logs and see what is there.
How many authors have asked SPECIFICALLY for her advice?
More than I can count.
How many of us would find that one of the greatest compliments is to get a good review on a fanfiction from her?
How many of us wish for an "Alternate history" series that is based upon what we wrote?
And her influence is not confined to Ranma, but also to Mystic Justice, A Ninja's Tale, Sailor Moon, and Bubblegum Crisis, and perhaps even Star Wars.
Thinking about her sig, the beginings of wisdom is the ability to ask questions, is what she does best. She forces us to ask questions about how we write, what we write, and why it is.
Let's hear it for the biggest influence in writing today, Ichinohei Hitomi