Along the lines of building an audience pre-publishing, the second edition of nickd's book about interaction design, Cadence & Slang, is currently on Kickstarter[1]. (I'm a backer)

In this case, he's used kickstarter to be transparent about costs and process. He can also offer preview content pre-release to people who have put money down to prove their interest.

[1] http://www.kickstarter.com/projects/nickd/cadence-and-slang-...