Trebor Scholz has aggregated a brilliant set of missives on continuous partial attention, which I think is a tremendous problem today.

"Continuous partial attention describes how many of us use our attention today. It is different from multi-tasking. The two are differentiated by the impulse that motivates them. When we multi-task, we are motivated by a desire to be more productive and more efficient. We're often doing things that are automatic, that require very little cognitive processing. We give the same priority to much of what we do when we multi-task -- we file and copy papers, talk on the phone, eat lunch -- we get as many things done at one time as we possibly can in order to make more time for ourselves and in order to be more efficient and more productive."