I'm an Evernote user from the early days. Tagging items has been something I'm accustomed to for a long time. I'm bummed that Dropbox isn't taking full advantage of these. They are not easy to get to in the web interface at all. I count at least 3 clicks, and none of those clicks are "Tag..."
Once something is tagged... am I just missing something? It's not evident at all. They aren't distinguished in a "bubble" or "block", color coded, and no option exists in the sidebar. I also cannot add the tags to my visible column set (also really lacking area). The only place I've discovered that tags actually exists in the web interface is under the search bar - but not at all where I would expect to see them in the application.