In his email newsletter, Seth Godin made the excellent point that
"What you write is directly related to who you are writing for, and deciding to publish has nothing at all to do with deciding to write. Publishing is a business decision, a financial risk and a marketing project. If your goal is to generate reach, to share your gifts and your point of view, you can skip all of those and just give your work away."
Now I'm not suggesting that you give your work away--although writing a blog like this is one version of giving your writing away. But I do think that it's more important than ever to give careful thought to how you want to distribute your writing, simply because there are so many more options.
You could go the traditional route and find a publisher.
You could self-publish by getting the book printed in quantity and sell them yourself.
You could self-publish using print on demand.
You could self-publish using only digital files (e.g. PDFs or Kindle format)
You could create an audio book and put it on CDs or distribute it digitally (mp3s).
You could put it all into a blog.
There are even more options--graphic novel format, videos, hybrids...
The key isn't so much what you are writing but rather for whom you are writing and how you plan to reach them. If you have strategies for that, the next question is whether you can get them to pay you, assuming that's important to you. And if you have good strategies for that, too, congratulations!
The point is that rather than rushing into the business side of things still wearing your writer's hat, put on your businessperson's hat instead--we need both.
(My book, "Your Writing Coach," covers not only writing but also marketing what you write. You can get it from Amazon and other online and offline booksellers.)