Webab

Webcal allows you to subscribe to other people's or public calendars. I wonder why there is no similar thing for address books (webaddr)? Or have I missed it? Imagine, if you could subscribe to your address book on some social networking website and never have to worry about phone numbers and email addresses being obsolete as long as your contacts keep their profiles current (and now they will have an incentive). Imagine, if you could update your own contact information in one place (perhaps, your local address book) and have it pushed to all your contacts automatically and unobtrusively. We already have all the bits and pieces in place, so the only task left is to repackage and popularize it.