I would guess that only the ninja at the battle knew, and while a few ppl might have told, i would bet the secret it still only amont ninja, not regular people. otherwise would the ramen guy let naruto ever come to the store? i doubt it.

also why would the jounin be suprised at naruto's power. now of course the 3rd recognized the power and new immediatly that naruto could channel it, his suprise was at who could have trained him. the jounin couldnt even fathom what that strange chakra was. This is a strong indication that not all ninja know, but rather elite ones at kakashi's level i would guess. now toothpick guy is a jounin, and the two sitting beside hinata i would guess are also jounin. few seem to actually understand kyubi's power and naruto's relationship to it. even the two jounin that were training the other two teams were suprised at naruto's ability. the female jounin (although newly raised) was expecting kiba to win.

now this could be attributed to the fact that no one expected naruto to be able to channel the kyubi's power even if he had it in him, except for the elite who understood the seal better. i seriously think less people know that we should assume. True all the parents 'hated' him but maybe they didnt know fully why. people make assumptions on little information and others suffer for itall the time.