How do you find hiring? A Blekko founder said they chose Perl partly because as one of the few hot startups to be using Perl, it would make them a top choice for great Perl hackers.
Unless you're talking exclusively to language/stack zealots, the best guys are evolving the tools, and the next-best are evolving with them. That's not to say that all things old are bad and all things new are good, but we do tend to get better at different classes of problems.
As the author suggests, though, Perl has this incredible longevity and extensibility. I really like it whenever I work with it, and it wouldn't be a turn-off if I was considering working there. But if someone came to me and said, "I want you to develop a To-Do web app in C++," I'd probably pass.
Perl was one of the first mainstream advanced scripting languages to run the Web, so the amount of folks out there that cut their teeth on CGI/Perl is pretty wide and deep.
For me, I started writing my first Web apps in Perl, and moved over to PHP.
So far hiring hasn't been a problem for us. However, we don't focus on hiring Perl hackers, but outstanding hackers instead. They grow to enjoy Perl after a few hours and sometimes during the interview ;) haha
Getting attention because you didn't use Node or Clojure or Erlang or Ruby or Python or Java is trickier.
(I've been at this long enough to remember hearing from VCs "Your product has a Perl backend and a Python frontend? Oh... would you consider rewriting it all in Java? Java has more buzz.")