well as far as I know there have only been one or two studies of this correlation and none of them were published which in the review book I have access to is assumed to be because of lack of clear findings.
but if you can provide me with a scientific study which says otherwise then I stand corrected.
Aie, ok, I'll see if I can find some time to look through all these things again. Yall are going to make me old and gray you know. I'm positive I've done it for both of these topics already... but since I can't find it... meh.
Ok, I've looked it over... I don't see any heritability studies for MBTI that are peer reviewed, so I'll amend what I said - within the FFM, there is lots that says similar traits are heritable

I'm pretty sure I had a MBTI study from CAPT/CPP, but it'd be at work if I did.
So, within that (listing only abstracts for now);
The heritability of conscientiousness facets and their relationship to IQ and academic achievement;
All conscientiousness facets were influenced by genes (broad sense heritabilities ranging 0.18-0.49) and unique environment, but common environment was judged unimportant.
Heritability of facet-level traits in a cross-cultural twin sample: Support for a hierarchical model of personality.
Additive genetic effects accounted for 25% to 65% of the reliable specific variance. Results provide strong support for hierarchical models of personality that posit a large number of narrow traits in addition to a few broader trait factors or domains. Facet-level traits are not simply exemplars of the broad factors they define; they are discrete constructs with their own heritable and thus biological basis.
Heritability of the big five personality dimensions and their facets: A twin study.
Broad genetic influence on the 5 dimensions of Neuroticism, Extraversion, Openness, Agreeableness, and Conscientiousness was estimated at 41%, 53%, 61%, 41%, and 44%, respectively. The facet scales also showed substantial heritability, although for several facets the genetic influence was largely nonadditive. The influence of the environment was consistent across all dimensions and facets. Shared environmental influences accounted for a negligible proportion of the variance in most scales, whereas nonshared environmental influences accounted for the majority of the environmental variance in all scales.
Yes, please do so

I understand the matrix of generation heredity is complex. I have looked at some studies of this myself which conclude that here is no heredity at play within the MBTI. Jung also says that type changes through the course of life, just like early Myers-Briggs practitioners believed that type could changes around 30 and around 50.
Type is suppose to not change... although you are right, this is starting to change (since the validity in MBTI isn't super high, I guess it's the alternative to saying that the theory is wrong, heh). I always hated the "develop other functions" stuff.
Also, most positive MBTI studies out there are sponsered or conducted by CAPT. that's alot like big tobacco scientists "prooving" that smoking isn't dangerous, isn't it?
Not all, there are other peer reviewed papers out there... however, I never claim anything within MBTI unless it has also been shown in FFM or similar. Having said that, IQ is heavily emphasised in MBTI N because of the population distribution.
Anyway, here's the paper;
The relationship of the Myers-Briggs Type Indicator (MBTI) to IQ level and the fluid and crystallized IQ discrepancy on the Kaufman Adolescent and Adult Intelligence Test (KAIT).
The thing to note, for those that aren't able to read it, is that it is
more accurate to say that Ss compose a large percentage of lower IQs than Ns, not that Ns are "smarter"... although they are significantly over represented.
This is another one of those data problems... it is correct to say that if you take a random N and a random S, the N is very likely to be smarter than the S. However, if you take a random smart person, they are not significantly more likely to be a N than a S (about 50/50, despite the 30/70 mix).
(The sample was also somewhat biased, but shouldn't significantly impact on the IQ - N effect, as can be seen from the % population numbers in the sample. But I'm not getting into the age effects on MBTI here

)
I've only read about the FFM having slight correlations with IQ score on the Openness factor. But despite an alleged correlation between Openness and N, I see Openness factors that are also favorably correlated to S (aesthetic experiences and sensitivity to beauty), F (emotionality), and P (adventurousness).
It is significant, but you are right that it isn't terribly strong. Worse than that, a lot of tests operate not on IQ but a form of concientousness, which is more predictive than IQ for academics and some job peformances...
But interpreting this stuff starts turning into a full time excersize (for anyone that wants to read it,
Prefrontal cognitive ability, intelligence, Big Five personality, and the prediction of advanced academic and workplace performance..
(If more details on anything I listed are needed, I'll do what I can. For now, I'm going to plan a wedding.)