So everyone's talking about how much work they can get done and how great they are at multitasking. But are they really getting anything really "done?" Seriously. If you think you're working on a bunch of things at the same time, take a moment during the middle of it all and ask yourself "What am I working on right at this very moment?" Your honest answer will more than likely be "Well, I'm on the phone and then I stop listening so I can send an IM to my other friend" or "I'm checking some spreadsheet calculations and then stopped because someone just stopped by with a question" or "I keep trying to finish this task but I keep getting interrupted so I never got it done."
Your brain is wired to completely devote attention to one conscious thing at a time and also to quickly move from one task to another; but it's not occurring at the same exact moment. We demand so much from ourselves that we've even convinced each other that multitasking is the goal of an efficient and effective mind. Checking your cellphone while at dinner with a friend, taking a phone call while you're having a conversation, driving and texting; these are examples of very common behaviors in society that may have already become acceptable in your circle. My question to you is should they be acceptable? Are we really able to share our time with others if we're not fully engaged with them? Can we truly communicate consciously with others if we're breaking away to give attention to someone or something else? Are we putting our attention to the more critical tasks at hand rather than something that can really wait a few more minutes?
Others have addressed these thoughts in creative and thought provoking ways.
Multitasking or Task Switching