This clearly can be very beneficial for advertisers. Now it makes a lot more sense to me how Facebook makes so much profit. Before I never really realized how they were getting that much money. I think that they should make it more clear to there users about how they store and use their information otherwise it is unfair to do so without permission. Everyone knows that there information is out there, but I don't think we really realize to what extent.
It would be really interesting to find out which information they keep and why. While browsing my information I saw that there was some info missing. I was really confused as to why that was missing over other things because I feel as if some of that data would be more beneficial for Facebook and their advertisers. Also, I would like to know how much data they are willing to store per person and how long.
Overall, I guess it is somewhat surprising, but it doesn't really bother me. I don't post anything private on my Facebook. I believe there would be a lot of people out there that would be truly bothered by this though.