Those of you who follow Getting Things Done know that you don't manage time, you manage tasks. Scott says he "thought [time management] was all about being organized and careful planning", but "the number one thing you can do to . . . is be very selective about what you choose to do."
As Tim Ferris said, "time without attention is worthless, so value attention over time".
Steve Gillmor has long talked about attention data as an asset and recently discussed that the impact in Microsoft's attempt to purchase Yahoo. Google is the king of this, putting things out for free and monetizing the time and attention of its users, and Newsgator recently started offering their software for free and are using this valuable attention data. And as Kevin Kelly said, we're in a world where inputs are increasing and time and attention are not. Thus, time and attention have become even more scarce and valuable than they were in the past.
The same lessons are appropriate for productivity as well. Since time and attention are an ever scarcer resource, the answer is often to be selective of how you deploy those resources.