Google has most all of your information already…
BUT how they are about to use it should have you concerned!
Some email services, like Gmail, actually read the contents of your mail (both sent and received, even if you aren’t a Gmail user but just sending to someone who is) in order to decide what kind of ads to serve up to you. They may call it “scanning” and attempt to equate it with less invasive activities like “checking for spam” but it’s quite different. For you, and the people you send mail to, it’s not spam, it’s personal.
Further, people tend to stay logged into their email service throughout the day. So all Internet searches you do with Google become tied to that same identity.
Finally, whenever your Gmail account is logged in, videos you watch on YouTube get connected into that same profile. And it’s worth noting that while Google has recently claimed they “aren’t doing anything new,” it’s clear from their letter to Congress that their new policy allows them to cross-index your YouTube viewing information with your Google search behavior (something their policies explicitly prevented them from doing until these new changes).
So what looks on the surface like a simple choice of email provider has an iceberg-size set of implications below it. Since their announced changes provoked a backlash, Google has been trying to characterize them as “simpler,” “easier” and “more consistent.” And finally, they keep trying to assert that they haven’t made it any harder to control what gets collected about you.