you don't manage five minutes and wind up with six; you don't manage information overload - otherwise you'd walk into a library and die . .. you don't manage priorities - you have them.The Wired writer, Chris Hardwick, compared GTD's readability to a camera manual, and while it isn't that bad, I'm going to have to suggest listening to the audiobook. That way you can do other things at the same time (bonus points for getting things done!) and you won't fall asleep.
The goal of following the Getting Things Done system is to get everything off your mind, so you can relax and get into your most productive state (the chapter on having "a mind like water" was excellent). The premise of the book is that all the unfinished things that you need and want to do nag at you and cause stress, unless you put all of these things down in writing in one place where you know you will see them frequently.
Allen's other great idea is to make a list of next physical actions for each of the projects that you put on the list. When you find yourself with unscheduled time, you can work on whatever is most urgent or suitable for the length of time that you have. If the next step is something that can't be done right away, you put it on your calendar or on your list of things that require action from other people.
One of Allen's clients called her to-do list before she went to his seminar "an amorphous blob of undoability". So was mine, and it was only a third of the length of what has become my projects list. The sheer size of it means I'm going to have to decide what's really important to get done (note to self: get a medical directive before learning how to Rollerblade).