As a user? I don't care a lick. Of course we can map any kind of relational system into a series of strings. What matters is support to do it in an intuitive w

As a user? I don't care a lick. Of course we can map any kind of relational system into a series of strings. What matters is support to do it in an intuitive way. Nested folders are intuitive, in terms of organizing, browsing, and highlighting the existing structure when adding new items. Tags fail at least at the last two without UI support.