I don't like it because it's very wasteful of screen real-estate. I do want to see directory hierarchy, but I don't want my files list to be squeezed into smaller and smaller space so I can see lists of every sibling folder of every folder in the path down to the folder that I'm viewing. This view isn't useful in proportion with how much space it takes up. IMO, access to directory structure works better as a treeview, separate from the 'current folder' view, rather than as a new column for each step down into the hierarchy. The latter doesn't scale well.