I've always enjoyed the Myers-Briggs Personality Type System- it seems like a great way for people to get a very good basic understanding of why we are the way we are. In fact, I hope it's someday taught to everyone in public schools, not just in some college disciplines. Perhaps there would be a more enlightened overall view of how human beings function individually and together. Instead of saying...'he's always late', you'd say, 'oh, he's a strong Perceiver'. Likewise, if you thought your significant other were being judgemental, you'd give them a big kiss for their strong Judging abilities instead of storming out of the room. Granted I pointed out a couple of areas that can cause friction, but that's just the point- we'd have a common understanding about eachother. We'd know when to be more or less aggressive based on our own type in relation to the type or types we were dealing with at the time. What once frustrated us could become fascinating, and people-watching could become a national sport (as if it's not already;).
Back to GTD: Recently, I've been wondering who gets more into GTD: Perceivers or Judgers? A lot of judgers I know are always looking for anything that will help them go that much faster, and many perceivers I know are yearning for a system that will help them make their open-ended ideas into reality. I did a Google search on it, and found a good dialogue at the DavidCo forums, which you can checkout here. After having read the forum, I'm convinced GTD is flexible enough to be appealing to adherents on both sides of the personality spectrum. Judgers become that much more efficient, and Perceivers have a system flexible enough to allow them to follow their inspiration. I thought I might find a strong bias one way or the other, but in the end, I think we're all trying to get done what's important to us.