If the more public option is the default, then you can not claim to be "private by default." Further, if someone else can invite others to see something of mine, then you are removing my control of privacy.<p>My personal view is that if you put something on the internet, it's not private. My Facebook account and everything I put in it are public - I find it's easier for me to answer the question "Do I want the whole world to know this?" versus understanding the complicated network-visibility rules in Facebook. In other words, I don't fault Facebook or Twitpic for defaulting to public options. But don't <i>claim</i> that you default to private do when you clearly do not.