|Here is a nice article related to the PHP market - it analyzes Freelancer Jobs in a popular Freelancing platform and it's evolution betweend 2001 and 2008|
As you can see the most cash runs into PHP jobs, and only JAVA keeps the same trend as PHP - but on a lower level. The big inflection point is in 2004 when PHP5 was launched. It seems that the release kicked the PHP market up
Anyway great article Manuel!