Automatically followed by abusive ex-husband (and his friends) on Google Buzz
Google adds opt-in on sign-up, and easy opt-out later ("Disable Google Buzz Completely" in Gmail settings):  <a href="http://news.ycombinator.com/item?id=1123873" rel="nofollow">http://news.ycombinator.com/item?id=1123873</a>