With the use of custom taxonomies we should have easier access to our taxonomies. Take the following:
'categories' is taxonomy, therefore we should be able to use the function for custom taxonomies like the following:
wp_list_[MY CUSTOM TAOXNOMY]()
This is common feature in other frameworks and one that if WordPress had would make working with custom taxonomies and post types even easier.
Here is some documentation on ZendFrame work and there use of magic methods:
Does WordPress plan to support anything like this in the futue?