>What you are scared of is some hypothetical situation that there so-far is no evidence it could happen
Ecio78 outlined a scenario in which relevance targeting "outed" him in a way he didn't want. I'm analogizing Facebook relevance ads with Gmail and search ads.
I didn't think Ecio78 was saying that emails are going to pop up explictly, only that Google would present information that is relevant to him in a situation where he didn't want that relevant information.