I was having some conversations with some people who I thought were of various types, and came up with the following broad generalizations of how NT types may appear in conversation. See if you agree.
In talking to INTps, it seems that they have views about specific "content." They have an idea of what "reality" is. They might say something like, "the news reports may give you this impression, but if you look at the whole context, the entire history, you'll see that it's really like [such-and-such]." In making their arguments, they like to appeal to the idea that if a person were to see all the information, that person would come to a certain conclusion. Often, this creates the impression that the INTp has a tremendous store of knowledge; yet INTp's ability is more in seeing the pattern, the trend, the insight, that comes from knowledge, rather than merely knowing lots of facts.
In talking to INTjs, it seems that they have lots of interests. They may be interested in math, computer programming, music, and other endeavors that involve creating with structure. However, they also may tend to be a little reticent to share specific unique views the way INTps do. They have a high logical standard that keeps them from making statements that may be incorrect. If they do voice opinions, they may seem firm and absolute, since they see these as based on absolute logic. Sometimes they may appear to put a lot of energy into pointing out a distinction that seems to be about something rather small or trivial to others. This is because they'd rather be absolutely sure about an obscure or minor point than say something stupid about something more far-reaching.
ENTps seem to like to talk a lot about reinterpretations of reality....e.g., Everyone thinks that white is white and black is black, but really black is white. They like to make paradoxical statements, or statements that show that what people often think is good is really bad. They tend to have lots of enthusiasm about their ideas, but over time they may jump from one idea to the next as if the old one really doesn't matter that much.
ENTjs tend to make discrete, logical-based points about things. They're very open to logical debate and discussion, because they can always come up with a reason to support or challenge any viewpoint. They may identify themselves with a certain way of thinking...e.g., a certain philosophy or theology, a certain school of thought, a certain corporate position; they may differentiate this from competing schools of thought that they disapprove of. Overall, one gets the sense that they believe they must make choices, accepting this way of seeing things and rejecting some other way of seeing things. They try to ground their reasoning in far-reaching inductions that allow them to seem quite certain about a particular viewpoint.