Here are a few points off the top of my head. Most or all are opinion only, with perhaps little or nothing factual backing them up:
- it's open source and free, so no cost here
- Perl developers are in large decline since its hayday, so the cost of maintaining existing codebases or new code projects may/will be higher in this regard
- it will be much more difficult finding quality Perl programmers than it may other more cute/fad languages (Python etc). That said, Perl devs are Perl devs... most of the highly experienced ones don't jump from fad to fad, doing only a couple years in between moves (when they do move, most stick with Perl on the side)
- Perl is partially based on the C language, so experienced C devs can pick up Perl quite quickly
- Perl is a Do What I Mean language
- Perl's main slogan is TIMTOWTDI (There Is More Than One Way To Do It), meaning that it's one of the most flexible languages out there (at least all the ones that I'm fluent or partially fluent in)
- The, or one of the largest online databases of free, Open Source modules all in a single location, makes installing and using new APIs/functionality so simple even your grandma (or your GrandFather) could do it (CPAN)
- it's Perl, it's the best language ever written!
- it was designed by an expert linguistic, so the language is exceptionally easy to understand flow
About to start a meeting, so that's all I've got for now.
update: Added GrandFather in there, because, you know, he's a real edumicator here, and thought it fit (while replacing a brake line on one of my trucks of all things :)