It's easy to see why a writer would want to do it though. Most of the time you write a book, it goes out into the world, and you have no idea what anyone thought of it. Hearing from readers would satisfy the natural curiosity of authors.
Nieman Journalism Lab has an article on how Amazon is changing what the book is all about.
I hated much of the tone of this article because it is written in my least favorite language: market speak.
There are a couple points to note here. First, most obviously: @Author represents yet another step in, yep, the personalbrandification of the publishing business — book-wise, news-wise, otherwise. The title of Amazon’s new feature, after all, isn’t @book or @genre or @publishinghouse; it’s @author. The identity of the author herself — as defined and measured and bolstered by her ability to create a community around her content — is, here, itself a kind of product.
Having people who respond to what you write, and who develop and interest in what you might put out, is not "creating brand identification." It's building an audience. In simpler times, what they are calling a "brand," or a "product," Dear Reader, we once called "a reputation."
The idea that readers would connect with authors rather than publishers is nothing new. I venture to say that even in the brick and mortar days of book selling people did not go in looking for a book from their favorite publisher.
My perspective on the whole publishing industry is quite simple: authors and their stories, in whatever form, do not exist to support an industry called "publishing." Publishing is the industry that came into existence to fulfill the desires of readers to have access to literature, to support writers enough so that they could create said literature. The successful business models of the future will be the ones that keep that original mission-- connecting readers to literature.
I do realize that my backwards take on things-- that the money making part of business is a byproduct of making products and services available to society, rather than the other way around-- is probably why I wrote a book called "Broke is Beautiful" and not "How I Became a Millionaire Through My Idealism."
In any case, the Nieman article proposes that this assumption, that the author will continue to be available to the reader after completing the book, changes expectations about what a "book" is about. A book becomes a dialogue, never entirely finished and closed. It seems likely that the ways we conceive of "books" and literature will evolve because of this technology. This is an interesting development and we'll see where it goes.
One potential problem I do see with this "digital commodification of authorship that takes place by way of community and conversation," as the article puts it, is that letting readers ask authors whatever they want, ironically, risks diminishing the role of the reader in the literary process.
Here is what I mean: The writer of a book, especially a fiction book, is only half of the literary equation. Much of the meaning of a book comes not from what the author intended, but what the reader brings to it. There are as many takes on Hamlet and Jane Eyre as there are readers to come into contact with them. The writer might have a strong idea of what a character's motivations are, beyond what is literally present in the text, and the reader might have a different idea. Who is to say that the author's idea is the right one?
Being encouraged to ask the writer limits the role of the reader by bringing the author back in to "settle" some of the questions raised by a book. Sometimes the questions are more interesting than the answers.