Great points, Haywood. You're right that book sales and job postings may not be in step, and the fact that there's an increase in interest in other languages by book buyers is just one data point. We're actually trying to do some studies now on the relationship between job postings and book sales. This topic is very interesting to us as well, because, as you say, we make most of our money by selling books. But I want to be clear that we don't have any agenda here -- we're an equal opportunity promoter when it comes to technology.
I'll also note that there haven't been a lot of new perl books for a while -- and we just released two wonderful ones: Advanced Perl Programming by Simon Cozens, and Perl Best Practices, by Damian Conway. I'm very much hoping that those two books move the needle significantly, and we see a nice uptick in the Perl book trend line as a result!