Something is deffinately up with Sasuke.. Hashirama, Naruto, Shikamaru have notice it.. If he kills or in the current situation (he tried) killing the juubi that means killing the Tailed beasts ,which include Naruto as well..
Sakura, well i think that she knows something is wrong, and thats bothering her the most. If she heard Sasuke's words she may realize now his intentions , but thats my assertion.
Her feelings however begin to falter , even Sai saw it.
This does not prove NaruSaku , nevertheless if Sasuke does what i think he wants well that much guarantees the fight between the two powerhouses-right?