We often hear the comment, "No IT Manager ever got fired for picking Java." Why is this? Java is considered a safe choice because it can solve many problems and it has sufficient market penetration that it currently is not viewed as a risky choice.
I compiled the following in an attempt to show that no IT Manager should ever get fired for chosing Perl either. I am not trying to write a justification for why Perl is the best choice for any given IT task. Rather, I believe the evidence listed below shows that it is a perfectly acceptable choice and should be considered on even ground with other possibilities.
Given this information, a responsible IT Manager should proceed to select a language or programming platform based on things that actually matter like the task at hand, the budget, the current skills of the target coders, the current environment, etc.
I present it to you, esteemed monks, for input and review.
Aptitude for the task:
The main point of these stats is that Perl has a large and broad user community. With any technology you choose, you don't want to be the only one using it. These numbers show that Perl is still widely used for web development, among other things, and the user community is very active.
Note that perl, mod_fastcgi, and Embperl are all Perl-related web technologies. (Note: mod_fastcgi is not exclusively a Perl technology.)
Notable Perl users:
Perl is used by Amazon, Google, Yahoo, and Ticketmaster.
Perl, Apache, and related technologies are open source and free. On-going overhead cost to vendors for code that continues to run is $0.
Recent Bookscan stats show Perl at roughly three times the number of sales as Python, ten times as Ruby, and half as many as PHP.
O'Reilly Media is very much driven by numbers and they felt the Perl book market was strong enough that they published 4 new Perl titles last summer alone. That is a large number of books for a relatively small tech publisher to devote to a single language.
There are many sites on the internet that post Perl jobs and they all more or less reflect the numbers listed at http://jobs.perl.org/about/stats
Some other jobs listings:
Basically, the number of companies listing Perl as a job pre-requisite is large relative to other technologies and has been consistent.
Perl continues to be actively developed. Many developers are working on Perl 6, the next major version of the language. At the same time, dedicated teams continue to fix and augment the Perl 5.6, Perl 5.8, and Perl 5.10 releases. Many companies would have de-supported these version rather than maintain them. The fact that you can safely continue to use a production release of an older Perl without being forced to upgrade is a strong feature.
Release dates are available here: http://perldoc.perl.org/perlhist.html
Perl is also very mature and stable, and has been running on large production systems for years.
Other sources for Perl information:
Nice summary here too: http://perltraining.com.au/whyperl.html
Update: Clarified that mod_fastcgi is not Perl-only and started a list of other jobs sites.
Update: Changed 'fix' to 'modify' in the Open Source section.
Update: Now posted here http://www.perl.org/advocacy/whyperl.html also.