There are some pretty harsh things said about ENTJ's and ENFJ's on this thread....wow. I will say that as a person (not necessarily because I am ENFJ) I am very interested in introspection and growing as a person. I am also interested in others and generally consider myself to be intelligent. I did earn a Master's degree, so I have some proof to back this second claim up....
My main point is just that saying people are selfish if they are XXXX, or obviously stupid because they are type XXXX, is pretty ridiculous. People are ultimately individuals. That is one of the things I love the most about the human race is that we are all a mixed bag to some degree. Some of whatever MBTI type are going to be butts and some are going to be awesome. That's just statistics.
As to the original thread questions of why there are not more ENTJ's and ENFJ's? I would guess that as to ENFJ's it is because they are on PerC, or have not yet discovered MBTI. I know all of my friends are likely tired of me telling them how interesting I think the MBTI 16 personalities are (and the interactions!), and I need to go on here so I limit my bugging them.
I think it is very likely that my father is an ENTJ, and my guess as to why he is not on here is that he is too busy with all of his projects (he is always building something) and then telling other people about the projects.
Edit: Just realized this thread is SUPER OLD. Ooops. I was interested in the debate and did not pay attention to the dates.