Sasuke doesn't know about it, if he did, then he wouldn't have run off to Orochimaru.
Sasuke hasn't seen a few stages in Naruto's development, he didn't see him kicking Haku's ass (which is a good thing) he hasn't seen him fighting neither Kiba nor Neji, he doesn't know he fought Kabuto (actually, he doesn't even know Kabuto is evil) from sasuke's point of view, Naruto has gone right through the loser child in the academy, to saving his ass twice (2nd exam, and gaara fight) with 'magic' power, stole his life perpouse (in the Itachi incident) and even outdone him (hospital fight).

and since Sasuke believes in blood rights and supremity of bodies, he knows that something isn't right in the leaf if Naruto (the supreme looser) is getting stronger than him (the heir to the Uchihas), and when someone presents him the oppertuinity to get stronger in a short time, while throwing in some carefully thought of remarks (the potentiel crap, and what the sound 4 said), Sasuke goes crazy to restore his pride as superior, and runs off with the sound...

if Sasuke would have known about the fox, he could have said to himself that it's only because of the monster that his brother is so intrested in Naruto and that the only reason Naruto grows stronger is the fox.

that would be a perfect lie that he could tell himself while he's angsting about his family instead of doing real trainning.



about the rest of the genins, i reckon that only Sakura, Kiba and Neji would be able to see through the fox and believe that Naruto's strenght comes from him, and not only because of the demon,,,, actully, i'm not sure about Kiba, he has a 50\50 chance to understand that, it all depends if he lives to that point. Shikamaru isn't in the list becuase it would be too tiresome for him to change his attitude towards someone.

And Hinata? i thought it goes without saying, but since i'm already saying it, then i'm sure she won't change her behavior towards him, maybe she'll even use this chance to get closer to him...