It was just last December that Tim O’Reilly said that Ruby book sales had surpassed Python book sales. Now Ruby book sales have also surpassed Perl book sales.
Tim O’Reilly posted the graph below which shows the books sales since 2003 for the most commonly used dynamic programming languages.
Click here to see a fullsized version of the graph. Notice the rise in JavaScript book sales, too (obviously due to the popularity of Ajax).
UPDATE: Tim O’Reilly just published an annotated version of this graph (which I like even better), so I have updated this blod posting to use it.

The implication is not clear to me. It could be that there is more good gratis documentation for Python and Perl.
Man you don’t even know how long I’ve waited for this since disabling my own Movable Type widget (that doesn’t work since Haloscan bypasses that code).
We are currently doing a study of the rising popularity of Ruby vs PHP, Perl, and Python at http://www.odinjobs.com/blogs/careers/
vrotmnenogi