If you have a google account, you can use it at bookmarks.google.com. The web interface is primary, but if you have your bookmarks bar visible, you can drag the 'Add Bookmark' link to your toolbar, and it will place a button there that when clicked will popup a window that will add the URL of wherever you were when you clicked it to the page at bookmarks.google.com, complete with fields for title, notes, and tags. So each person's bookmarks.google.com page will have a list of tags and recently added bookmarks. It's very straightforward, and reminds of Bush's trails idea.