This may be better placed as a Meditation, but here goes...
It is written in perlstyle, "Call your subroutines as if they were functions or list operators to avoid excessive ampersands and parentheses."
Personally, I like using the ampersands for my functions and subs because it serves as a visual cue that it's my code being executed and not a built-in function or somesuch. However, I have heard other people refer to ampersands as being Perl4-ish and generally unnecessary in this day and age.
What are your thoughts? I await enlightenment.