Apenwarr's article about tracking, alogorithms, and personal data collection was a good read. It mirrors my own thoughts around this topic. I work inside the marketing department of a company that sells the product it manufactures online. I have been mystified why retargetting tactics are highly revered, when my own experience with retargeting is so lackluster on the receiving end.
I also like the explanation of why Netflix's recommendations are so much more lackluster than I remembered them being long ago. I had thought it was because my husbaand and I use the same account and our tastes vary enough that we confused the algorithm. That's not so. It's because it doesn't really matter what we might like. We're being given boilerplate items to make sure we keep our subscription going.