The title of the Naruto Manga chapter 578, “The Weakness of Despair” actually tells about the weakness of the Edo Tensei jutsu used by Kabuto in reviving the dead shinobi including Madara and Itachi.
According to Kabuto, the Edo Tensei jutsu has no weakness and no risk. However, the fact that it failed to control Itachi after reviving him is proof that the technique has a weakness. And Itachi is right, the very weakness of the Edo Tensei is Itachi.
This particular chapter of the Naruto Manga supposedly will tell us story of the 3 wars which is currently happening in the world of Shinobi. These are the wars (1) between Naruto, Bee, Kakashi and Gai versus Tobi and the path of Pains; (2) The 5 Kages versus the revived Uchiha Madara; (3) and the fight between the two Uchiha brothers, Itachi and Sasuke, against Kabuto.
But the latest released Naruto Manga chapter is just showing few updates on the first two mentioned wars, and it is more focused on the third mentioned war which is the war between the Uchihas and Kabuto. The war has not yet started. They are still talking. I guess the real fight will start on the next chapter of Naruto Manga, 579.
Sasuke and Itachi
This time, Sasuke is more friendly with Itachi. And there are many things that Sasuke wants to hear from Itachi. But Itachi would not tell Sasuke of the things he want to hear because Itachi want to defeat first Kabuto.
Sasuke was assured by Itachi that this time, when he promised it should be kept not like before that all his promises to Sasuke were all broken.
But the problem of Itachi now is, how should he defeat Kabuto without killing him?