The benefits and drawbacks of constant multitasking are complex, to be sure, but this article on how our multitasking might be affecting others is worth thinking about: The Broader Consequences Of Multitasking : 13.7: Cosmos And Culture : NPR
"In the study by Sana, Weston and Cepada, students who engaged in multitasking expected that it would hinder their learning a fair bit (a mean of 5.5 on a 7-point scale), but thought it would barely hinder that of their peers (a mean of 3.3). And in the study with multitasking confederates, participants estimated that seeing others multitask had barely hindered their own learning (a mean of 2.7).
Yet having multitaskers in view did have a considerable impact on learning. In fact, the negative consequences of observing multitasking were even greater than those of performing multitasking oneself (perhaps because the multitaskers could time their multitasking to suit their own needs), counter to students' expectations. Neither multitaskers nor their neighboring victims realized the cost of merely observing multitasking." Read More
The full text of the study is available here: Laptop multitasking hinders classroom learning for both users and nearby peers