I see Perl as an excellent language for stepwise refinement. You just write the damned script. And then later you decide to abstract domain-independent parts into modules. Then this same script can be rewritten with a clearer distinction between doamin-independent and domain-specific parts. And the domain-indepedent parts can serve well in applications because they have a well-defined general purpose.

For me, this has happened many times. I was re-writing a largish FTP application which was using Net::FTP. Common domain-independent patterns of usage led to my development of Net::FTP::Common.

On the other hand, we must admit something, no one is ever going to say: "write a script to compute the first N Fibonacci numbers." It is more likely that they will use the word program... I am not enough of a linguist to say why this might be, but there is something about this calculation that lends itself to be called a program instead of a script.