in reply to use PerlScript && die;
"Doctor, it hurts when I use Outlook Express!"
Seriously, though, you raise a few good points. But as with many things in life, this is a trade-off. PerlScript enables wonderful things like ActiveState's Win32::OLE Type Library Browser. And, for those who're motivated to do so, it allows the browser to be used as a very limited UI platform.
Trade this off against the probability of being attacked. Your average script-kiddie is unlikely to bother with a PerlScript-based attack, because percentages are so low. Unless they're targeting a Perl mailing list, the chance of getting hits based on a broadcast spam attack are pretty slim. I have PerlScript installed on my box at work. My work email address is generally unknown, and isn't on any mailing lists. I have no fear of attack there (except, perhaps, from my coworkers. But they phear me :-)