I think the main argument you'll hear about Perl being outdated is it's lack of good built-in object-oriented programming features. Turns out though, now that we have Moose, that argument has gone out the window.

Another argument you might hear is Perl 5 being outdated due to Perl 6 being on the way. That doesn't really hold water though, since there's just so much Perl 5 code out there. Also, it looks like you'll be able to access Perl 5 code from Perl 6 anyway, so the upgrade from 5 to 6 shouldn't be too bumpy.

Anyhow, if you like the idea of a handy, intuitive language that gets out of your way, you'll probably like Perl. PHP is popular with a lot of web developers, Java is popular with "enterprise" software managers, and .NET is of course popular with MS Windows people, but Perl is still the swiss army chainsaw of the bunch. You might also want to look into Python to see if it's your sort of thing. Python is like Perl's tightly-wound, responsible, predictable cousin from out of town who has a funny foreign accent. ;)