That is very subjective question. I know both php and perl well(not pearl, that is something you give your gf). Perl can become very messy very quickly and can become quite unreadable. But on the other hand, it is very very powerful. And allows you to do some powerful coding in a very short coding segments. Furthermore, it has been around for a lot longer that PHP. I believe that you are talking about a couple of things when you mention the perl in a web context. You are talking about mod_perl which is an embedded perl interpreter that is a module that loaded into apache at run-time. And db.pm for the database access and cgi.pm for the web end of it.
-HTH,
Tino