The last letter of a person's MBTI/jungian type seems to be the biggest difference in MBTI/jungian typology, that's because judgers prefer a in depth based approach(Pi) to taking in information and a breadth/more broad based approach(Je) to evaluation/organizing concepts/values while perceivers like the breadth based approach(Pe) to taking in information, placing more value on gathering as much information as possible from many different sources, even if it seems unrelated at first, but they have a depth based approach(Ji) to their evaluations, prefering a more holistic understanding.
I have even heard some comment on the subtle difference between judgers and perceivers in their posture, the way they carry themselves(this might not be the most accurate way to tell though). Judgers seem to have a more "solid, steady" vibe, like they seem more "prepared", while the perceivers might seem more "lackadaisical" and going with the motions. I think judgers might be more externally based overall because their judgement function is external, but the IxxJs can be very internal too though, so it seems the judgers might have more variation between the IxxJs and ExxJs. The perceivers seem more uniform in this aspect and they seem driven by novelty(of experiences, concepts, ideas).
I also notice a difference between Ji and Je, in that Ji seems to be more "fluid"(even if it might be against external standards) but Je seems far more practical(but rigid) in today to today activities, Ji by it's nature is also more abstract(esp. Fi), this can make it seem almost intuitive compared to Je. Do any of you have any thing to add, is this accurate or is it crap?