I've been doing pretty much just perl for over a decade. Mostly you run into the perl-only shops in web programming, or where a perl geek had flexibility to use whatever language, and chose to use perl (I did this a LOT in school, using perl instead of C, Tcl, Bash, and Sed).

Of course, you should only do this when perl is actually at least arguably the best choice (almost always :)

I'm currently working for StimTV. We use perl for a lot of the back end stuff.