Cool insights in Desktop! I really hope that someone comes up with a desktop metaphor for the hundreds of open browser tabs (which I think are the new bookmarks) that hang open in an endless horizontal list. Imagine tabs which are like documents, can be moved around, minimized, and spatially organized in folders and subfolders. Actually, why does this not exist somehow?
There's an extension for firefox called Tree Style Tabs. I never really got into it but some people are quite enthusiastic, pretty similar to what you describe though.
It may not be exactly what you have in mind but there is an interesting extension along similar lines (mostly for chrome) called TabFS that mounts your open tabs as a filesystem...
