Reality Mining: The future of marketing, or a privacy nightmare

I read an article the Marketing Profs Daily Fix Blog Titled: What’s Next for Marketing? Reality Mining, where Paul Barsch talked about how with the advances that have made in the cellular industry with GPS and internet enabled phones they have the potential to be able to mine more than just your calling info. MIT professor Sandy Pentland calls it "Reality Mining". He believes that they have to ability to record everything from your physical activity to your conversational cadences. With all this information at their disposal they have the ability to proivde customized plans based on all of these traits. As a marketer I feel that this is exciting news. We will have more advanced tools at our disposal to take behavioral targeting to the next level. We can further segment our audience and provide them with a more personalized marketing experience. But on the flip side of the coin one will argue that this is borderline invasion of privacy, and have the potential to compromise our personal information. Maybe cause I'm on the marketing side, but I don't really see any problem with this as long as the user is aware that this is going on, and have the ability to opt-out if they choose to. With the decline of mass media, its tools like this that will allow us to scope out that niche market that will actually find value in our message.