> People will pay for a half-assed book on PHP
This is an interesting tangent, and just as a corellary, I don't anymore. I find online sample code and community wikis a lot more engrossing and knowledgeable than single authors writing 300 page tomes of dead tree. Knowledge bases like the java and python documentation, qt developers wiki, etc are all much more useful tools for learning new languages, frameworks, etc than a big book on it, and I find wikipedia articles and Stack Overflow answers better explanations of broader concepts like variable capture or shared memory than a book on it conveys.
So I'm not buying books. I read a bunch in college (off the shelf in the CS lab), and a few were great, but I find myself getting much more out of collaborative online works than one mans ideas of the right way to do things (even when they have a dozen editors for reviewing).
But more on topic, and in a broader sense, I think we have finally reduced the cost of information to such an insignificant quantity that writing such books usually isn't a profitable endeavor. It takes radical success selling knowledge on dead tree to make back the time investment to write it all down, and people like myself won't even consider it because people will freely give their knowledge in smaller chunks (usually, there are plenty of books online for free, like Python the Hard Way) that the "industry" of selling knowledge is collapsing, in a good way. The challenge now is organizing the absurd amount of information generated into useful knowledge rather than actively adding more to the pile. It is a distribution problem now, not a creation one.