A thread on Slashdot alarmed me, just a little bit, for some minutes. Privacy is indeed a real concern when it comes to email management. When your [mine] gmail account stores gigas of personal emails, all legit stuff yet still private and by no means public!
The alert lady, "thanking" Google for its Buzz exposing her to some stalker, turned out to be her own many unthought-of clicks' victim.