A lot of comments seem to suggest people think the Microsoft employee used his work e-mail account and that's what Microsoft searched. That'd be one thing, but it's worth clarifying that Microsoft searched the BLOGGER's Hotmail account.
I'm surprised more isn't being made out of Microsoft's attacks on Google for privacy, going so far as to coin the term "Scroogled" for the way Gmail's automated systems parse e-mail content to deliver advertising. This sure puts that in perspective.
Biting the hand that feeds IT
