Of course, this means that a complete, and ever changing profile of you has to exist somewhere. I'm sure Google would be only too happy to collect that information.
In a sense, this is the idea behind groups such as those run by Yahoo! and Google. You
Think about the movies in which some fantastically rich person has servants who supply only the relevant mail, or only the interesting parts of the newspaper. That's what computers should be ... perfect servants. They should know exactly what we do and don't need or want to see, and present all of that, and nothing else. They should be omnipresent, and available all the time.
Wake me when we get there.