Pretty sure Naruto is going to teach him a lesson, and Sasuke is going to give up his lust for power.
Naruto seemed more annoyed than anything else at the end of the last chapter. Plus, Sasuke wouldn't go start his own village if he opposes the village system as it stands. Naruto is going to show him that he can create a new social system, and Sasuke is going to finally trust in Naruto (like everybody else).
Sasuke is likely going to give up being a shinobi (like Tsunade, Jiraiya, and Shizune) and opt to focus on rebuilding his clan or something. He will still have his abilities and be renowned throughout the world, but he will just be retired, in a kind of reserve status. The village can call upon him when needed, but he won't be going on missions on a regular basis.
He seems somewhat reluctant to step in to protect the village in the teaser quote. However, he clearly indicates that (since Naruto is away) he is more than capable of stepping up.
Another possibility is that Sasuke just goes to become a wandering hermit (like Jiraiya). Perhaps the hat is hiding a seal on his forehead (like the Hyuga).
