Ann_Smarty - 4:35 am on Nov 6, 2012 (gmt 0)
That URL seems to be indexed, and it can be viewed whether logged in or out at G+.
Found that option! It's under "Account" -> "Privacy and Visibility". You can include that part on your profile.
Since this is the first time I've seen the option and my own pluses are private, I guess the default of this option is that pluses are not public...