Thanks for a well written and balanced treatment. ++
Question: Perl OO being blessed references gives preference to creating HAS-A relationships whereas Ruby's 'everything is an object' should gives preference to creating IS-A relationships. Did you find this to be true? In other words, theory says that Inheritance should be cleaner in Ruby while Aggregation should be cleaner in Perl. For myself, I don't have any experience with Ruby so I would appreciate any insight you can give.