I have seen some other studies of personality types. I've looked at all kinds of quizzes. Most don't fit me at all. Astrology is embarassingly accurate. ColorCode is quite accurate, if you throw out the idiotic idea that only the highest-scoring color counts and instead treat them as percentages.
I think, if people are going to use any personality test for more than idle entertainment, it should be tested for accuracy. This is especially important given that corporations have gotten tired of using real interviews for job selection and are resorting to personality tests as a hiring filter. If the tests are bogus, then people are being denied a livelihood on spurious grounds, which is not a good thing at all.