yeah, salawa, those online ones are mediocre at best....I've never taken a real one, but my old therapist told me what was on it and demonstrated some stuff. there are four categories: verbal, spatial, processing speed and short-term memory. basically, visual is like the blocks and drawing pictures, i.e. attention to detail....processing speed deals with matrices and symbol-coding, short-term memory is where they say #'s, letters or both, in any order and you have to repeat them back....and then verbal is like metaphors and conceptual reasoning and vocab.
I would not be surprised at all if an ESTj scored higher on memory than an INTj....I think the visual fields are where NT's would score best, NF's might score higher on verbal....
In 'Zen and the Art of Motorcycle Maintenance', the author, Robert Pirsig, mentioned his IQ of 170 dismissively, saying the test was just analytic manipulation.