FWIW, this doesn't always work. I know of a certain columnist who took some of his columns and had them made into a book (via Apress). Well, nobody bought the book and he now has several thousand of them sitting in his garage. I picked up 5 of the books when he was giving them away, meaning to give them to coworkers two jobs ago. I forgot, and now they take up a lot of space.

(This was the publisher's loss, though, not his. That's the way to do things :)