We will have specialized services for this centralization(e.g GMail for email, picassa for photos) and also services that span multiple types of data. Thinking in these terms makes Facebook look a lot more interesting: it is a central place that hosts multiple types of your data in one place, and they are working on making it available to more screens - some of which are not yours!
He makes the argument that we (the consumers) are the product that Google and Bing sell, and argument already made for TV watchers. By the same token, a Facebook user is much more valuable than a search engine user because FB knows so much more about them.