Depends on how you like to work... and what you have to do.

Perl has broader abilities and finer granularity at the price of requiring more learning how to use its many capabilities (and it's definitely not just for CGI, web use or sysadmin chores).

PHP will likely have a shorter learning curve... but will also impose lower limits on the breadth and depth of you can do.

"(D)ebates" will continue until both have been relegated to history... at which time, the discussion will shift to the relative merits of Fluxicat2.1.3 vs. OOOM-III.