I'm still hoping someone can elaborate a bit on my third.
To be honest I'm not sure I understand it :-)
Do the Carbon API's or Cocoa framework take the place of some of the "glue" functions that Perl would have been used for when developing with C, C++ or Java?
Carbon/Cocoa are APIs to various Mac-like things. You can use CamelBones as a bridge to Objective-C that will enable you to easily (or, at least, fairly easily :-) get Cocoa and Perl to talk together. But I don't see how this relates to '"glue" functions that Perl would have been used for when developing with C, C++ or Java?' - or even what such things are :-)