>50% Gavin is Satoshi.
to anyone following the code and forum from early on, it's very clear that satoshi is not gavin, unless the rest of gavin's whole life has been an act.
he's also not schneier or any of the other frankly silly suggestions that people offer based on reasoning that can't be much more than 'i've heard of three cryptographers, so satoshi must be one of them'.
if you read his posts and code carefully and have some sense of these things, the impression you get is that satoshi is likely an oxbridge-educated computer scientist, maybe a graduate student or lecturer at a british university (or, marginally less likely, someone in industry with a bit of time on his hands. possibly google, since some googlers, depending on their circumstances, don't work very hard).
it's very unlikely that he's american or australian. it's inconceivable he's natively japanese, at least without having emigrated very early.
also, i doubt he's quite a libertarian, and he wasn't generally distracted by austrian-school ideology. i recall many times where he cut through various common misinterpretations of menger, for example, but not from the perspective of someone grounded deeply in economic terminology or fallacies. rather, he just called it out or ignored it as inapplicable to the questions he was answering. (the particular monetary policy behind bitcoin doesn't seem ideological but, rather, based in marketing and a sense of what would promote adoption. indeed, early messages from satoshi suggest that bitcion's appeal to libertarians was largely a marketing manoeuver.)
