And for those contemplating doing a Kickstarter, I'll just note that fulfillment really takes a lot of time. From ordering / producing various aspects of the rewards (aside from the actual book!), to gathering and organizing info, to physically shipping things out -- that alone has been at least twenty hours for me, I'd estimate. So figure that into your hourly value-for-labor estimate when deciding how much you need to raise to make the project worthwhile.
In some ways, it's very satisfying labor -- I really enjoyed signing and numbering the books, and I like thinking of all these rewards going out to individual people who supported the project. But still, time. Must be considered.