I have the opposite view - when I use Reader the folks at Google know how often I click on certain topics, and how long I spend reading each topic. My gut tell

I have the opposite view - when I use Reader the folks at Google know how often I click on certain topics, and how long I spend reading each topic. My gut tells me that such information would be quite useful to their search product, even if they have already know my search history. And for some users Google will not know their search history and social information. A similar logic applies to Google Checkout (aka Google Wallet). I would have thought that knowing my purchase history would be very useful to the search algorithm. So I really don't understand Google's approach. Their search algorithm is their prime asset, but they seem willing to degrade it bit by bit.