No doubt there are people who will disagree with me on this, but I quite like the books I've seen that started as blogs or Tumblrs or similar. The editor has a fine opportunity to see what the audience is, and a good idea of what a finished product would contain. And all that I have read so far managed to take what was a good idea and make it richer, deeper, more fleshed out.
As, for example, here. Because Bader Ginsberg has been awesome all her life. It was fascinating to see the trajectory of her career, and the progression of legal challenges to laws restricting women's rights. This isn't a traditional biography, but it certainly manages to hit a lot of high spots. And it also gives a wonderful insight into the ACLU and the directed plan to increase civil rights. I'd never thought about it before, but now that I know I love the idea of a career based on observing and fighting injustice. She has style, she has flair (those marvelous collars), and she has a keen sense of justice. The Notorious RBG was an entertaining and uplifting book. Every expansion in human rights is treated as something the privileged class just decided one day that it had to go. History classes (back when I took them) rarely or never portrayed the hard work, the organization, the PR, the constant ongoing struggle to achieve what has been denied. So seeing that presented in a zippy way with fan art, that is just a fabulous hook. I hope every young woman reads this and considers what she wants to fight for, and how, as well as how to accessorize her judge's robes. (oh, yeah, it feels a little Legally Blonde in a good way)
Not only was there a clamor at the house to read this first, but there was widespread interest among the librarians and patrons who saw the book. I can't fault any thing that gets people thinking about how to make the world better.