Tagging Google Earth
So, here's a question. With the usefulness of tags, or at least nonexclusive categories, proven to me (eg, del.icio.us), why none to help organize marks in desktop applications? I'm really looking forward to using applications that replace hierarchical storage of information with tags. For example, I gave up on storing bookmarks in browsers as soon as I found del.icio.us.Consider Google Earth. I'd much rather have a little search box, and a list of matches, in the Places pane, than the hierarchical tree under My Places. They use this kind of interface in the Fly To/Local Search/Directions pane, why not give it to users too? I can think of a half-dozen different ways to categorize any place on earth, so why do I have to shoehorn it in to only one place in the hierarchy?
Don't tell me to copy a mark into multiple folders. If I ever want the change the mark, then I have to hunt them down and change them all one-by-one. Aliases (symbolic links) aren't much better, because I'd have to create and maintain them. (Besides, I don't think Google Earth has them, so this is mostly an argument against symbolic links as a solution to the filing problem in filesystem directories.)
Even better, I'd love a dynamically-sized tag cloud that reflects my relative interest. Each word changes color if the tags are active. If two or more tags are active, then it shows only marks with all selected tags. There should also be a way to select tags to add marks, rather than match combined tags, perhaps by adding a plus sign before each tag like del.icio.us. In this approach, selecting another tag by the tag name adds those marks, but selecting another tag with the prepended plus sign limits the displayed marks to those with all tags selected.