"… we are so busy keeping tabs on everything that we never focus on anything. This can actually be a positive feeling, inasmuch as the constant pinging makes us feel needed and desired. The reason many interruptions seem impossible to ignore is that they are about relationships - someone, or something, is calling out to us. It is why we have such complex emotions about the chaos of the modern office, feeling alternately drained by its demands and exhilarated when we successfully surf the flood."

Nice description of continuous partial attention in this old New York Times article. I thought of it today in the airport when I eavesdropped on business people complaining (bragging really) about how their email piles up when they are out of the office. It says much more about their neediness than it does about their productivity.