Okay, haven't read any of the other posts yet.
Person 1: ENTJ
Person 2: INTP
Person 3: ENFP
Person 4: ISFJ
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Seen the results now and think I did reasonably well. Got one absolutely right, and was only one letter out on the other three. Here's my postmortem.
Person 1 (eNTJ) - I'm amazed that hardly anyone got this right. This just screamed out ExTJ to me, and very very likely ENTJ. Most of the guesses were ESTP, but I barely even considered that, didn't get that vibe at all. Little secret about men who aren't ESTPs: although some might not like to admit it, most at some point in their lives secretly wished that they were ESTP. Men acting like dicks in a showy, ostensibly ESTP way usually aren't ESTPs. I've only known a few ESTPs, so my sample size isn't very large, but they weren't dicks.
Person 2 (INTJ) - Fair enough. I know the schedule thing would appear a bit of a giveaway, but I just figured INTPs can have OCD too, and that the overall vibe was just more INTP.
Person 3 (ENtP) - Well, given that it's a small t, I was pretty close here. I went with f because ENTPs are all arseholes who don't feel a shred of remorse when they've wronged someone

Also ENFPs are perfectly capable of being into computer programming and such. And although some people seem to think that the insensitivity part doesn't fit with ENFP, I think that on the contrary ENFPs are more likely to invoke insensitivity in the name of being funny (I used to work with a really great INFJ guy who just couldn't reconcile my gentle eloquence and learning on a wide range of subjects with the torrent of abusive filth that would gush from my mouth just minutes later. I used to love how it drove him mad). So overall I got an ENFP vibe off the guy: ENFPs tend to be both the nicest guys
and the biggest arseholes, whereas ENTPs are just the biggest arseholes.
Person 4 (ESFJ) - Okay, even though almost everyone on this thread got this right, and the few that didn't opted for ESFP, I'm going to stick to my guns and say she's a mistyped ISFJ. I think part of the problem here is the automatic perception that talkative outgoing types are E's and that shy quiet types are I's. Of course, in most cases this is true, but not always because what really matters with this Jung lark is the use of functions. For me the stand out point here is that this is someone who obviously uses Fe a lot, but isn't actually very good with it, suggesting it's not her dominant function. Also, bear in mind that the original poster has admitted to not liking her very much, and this probably means he's not great at seeing the positive ISFJ traits that she may have (they're probably well hidden anyway if she has tested as ESFJ). Some of her negative characteristics remind me a little bit of my ISFJ mum's worst aspects (I should point out that my mum is a wonderful person). And despite being an introvert, my mum talks A LOT. Incessantly. I kind of wonder how she manages to breath sometimes. It can drive me insane -- and I often talk a lot too!