I've got this book I wrote. And what I'm doing with it, it wouldn't have worked 100 years ago. Hell, it wouldn't have worked 10 years ago. Self-publication, vanity publication, was a sticky and expensive process at best, and there wasn't necessarily much respect accorded to any of it. I've talked about this before. Yes, there are Eragon-shaped exceptions, but for the most part, it hasn't been the most dignified way to get your work out there.
And then the kindle showed up. And the nook. And the other 5000 e-readers. And the landscape is changing drastically. E.L. James drastically. [editor's note: no, I have no intention to be E. L. James. I'm a much better proofreader than that.]
So I've got this book I wrote. It's a book of short pieces - some full-out short stories, some poetry, some flash fiction (a page or less) - and I'm very proud of it. But it's a book I don't think I'd be able to sell to the middlemen of publishing - agents and publishing houses. It's too strange a shape for that. And that's fine. I've got this book I wrote and I'm digitally self-publishing, and I'm so glad I live now, here, in this time and place. This is the time for self-publication.