I stumbled across this great post by Robert Ghrist of the University of Pennsylvania. More people should read and follow it. I’ll add that I agree with nearly everything he says and add one additional positive that’s not explicit: by self-publishing on Amazon, you can also release your work electronically for free (if you so choose).
Robert also mentions that, “The truly difficult part of e-text production is getting something that looks really good.” True statement. Which is why aspiring authors should also use Rob Beezer’s PreTeXt, which leads to spectacular HTML output.
While certainly there are advantages to working with a publishing house for marketing and more, the new reality is that with Twitter, the web, and Amazon, good work has the potential to get known widely without having to have its cost ridiculously marked up by one of the big corporations. Seriously, if you’re working on a book, you should try out what Robert suggests.