How many of those jobs are for maintaining old PHP codebases written way back when, though? Basically, what is the ratio of "PHP the sexy web framework" to "PHP the new COBOL"-type of jobs. I can't imagine it's even close to 1.
Most of the jobs I interviewed for back then involved new development. The job I ended up taking turned out to be a ground-up rewrite of a consumer website (which sold for ~€250mm the week after I joined) to bring it from poorly designed PHP4 to better designed PHP5.
Why did they choose to do this in PHP instead of a more respected language? They already had a bunch of PHP developers.