I have always thought of myself as fairly outgoing, and being labeled as an introvert seemed strange to me. When I though about it, though, I realized that the test was (of course) fairly accurate in this assessment; I even recalled a few individual items on the test that proved this point -- my need to "reenergize" with some alone-time after hanging out with friends for awhile, or my preference for quite time at home as opposed to parties on many occasions (HumanMetrics 2011). I was not at all surprised to learn that I was a thinker, on the other hand, and remain somewhat uncertain as to the descriptions of being intuitive and judging. When I read the entries that describe the INTJ type, my assessment of the test, its accuracy, and its usefulness and relevance to my life changed dramatically. Often, personality descriptions (especially those based on pseudo-spiritual things like astrology and numerology) are so vague that almost anyone can see themselves described in them, but the descriptions I read of INTJs were very specific and directly spot-on. At several points in my reading, I found myself actually laughing at the number of things the description said about me that I had said almost word-for-word to others -- my desire for efficiency in everything I do and encounter, my extreme respect for knowledge and competence,...

More often than not I get frustrated when I go out in any semi-crowded area at how silly people behave when more rational behavior seems so obvious and so easy, and this desire and expectation for people to behave rationally is described as one of the hallmarks of my personality type (HumanMetrics 2011). I certainly gained a new respect for this tool after I had seen it in action (and an open mind that is always looking for new information is another INTJ feature!).
All in all, I would have to say that this test is astounding in its ability to determine the basic personality of an individual. The work that must have gone into developing the test and analyzing/describing the various personality types is enormous, I'm sure, and it shows in the simplicity and effectiveness of the finished product. Highly efficient, and thus highly enjoyable.

References

Boeree, G. (2006). Carl Jung. Accessed 1 October 2011. http://webspace.ship.edu/cgboer/jung.html

Hergenhahn, B. & Olson, M. (2011). An introduction to theories of personality (8th ed). Upper Saddle River, NJ: Pearson Prentice-Hall.

HumanMetrics. (2011). Jung Type Test. Accessed 1 October 2011. http://www.humanmetrics.com/cgi-win/JTypes3.asp