When Safari came out back in January, one of the features they touted was its "dynamic bookmark interface with a familiar single-window iTunes-like interface." Actually, here's exactly what the Safari site says (emphasis mine):
Many people don't even bother organizing their bookmarks because of other browsers' confusing, complicated interfaces. In Safari's Bookmarks Library, you'll find the familiar, single-window interface like iTunes, which lets you edit bookmark names and addresses in place as though you were renaming an icon on your desktop. You can create any number of folders in your library, and keep them in the bookmarks bar or menu, like the preinstalled news folder. ...
The problem is, Safari's bookmark features don't deliver on the promised "iTunes-like interface." The only resemblance they have to iTunes is the folder column and the contents column. Let's take the "iTunes-like interface" idea and run with it, and see what kind of bookmark management system we'd end up with:
The first thing we'd have to introduce would be the "Bookmark Library," which would contain the master copy of every item in your bookmarks. Each bookmark folder would then contain a subset of your Bookmark Library, much like a playlist in iTunes is a subset of your Music Library.
Your browser history would be automatically added to your Bookmark Library, so that an item in your history is in exactly the same place as any other bookmark.
In addition to that, we'd want to add a lot more meta-data about each and every bookmark. We'd want to add last visited, visit count, referrer information, how the site was left, keywords, comments, and even a summarized version of the text on the site (taking advantages of OS X's "summarize" service features.
Then, with all that meta-data, we could add "smart bookmark folders," like "sites I visit a lot but haven't visited this week," or "sites I visited that were linked from URL X," or "Prius sites I looked at last week."
Yeah. Now that would be putting an iTunes-like interface on the tried and true bookmarks interface, and it'd rock.