I was at the London Book Fair last week – and I’ll be blogging about that soon – when the news broke that David Mamet is to self-publish his next book.

His reasons? “Publishing is like Hollywood—nobody ever does the marketing they promise.”

While I think it’s great that someone as high-profile as David Mamet is self-publishing, I was very disappointed to find out the way he’s doing it.

Self-publishing is big business. By my estimates, self-publishers have captured 25% of the US ebook market. It can be lucrative on the individual author level too, with writers getting up to 70% royalties if they publish themselves.

The reason why those percentages are so high is that self-publishing allows you to bypass the traditional middlemen (agents, publishers, distributors) who each took their own slice of the pie before the author saw any money.

Literary agents in particular must be worried…