Never.. A novel completes within 600-700 Pages .. Naruto has now about 600 episodes... I dont see half of the story completed.. It will continue till we have Armagadeon.
Armageddon... my thoughts exactly >< however it allready seems like Armageddon xD
This arc now seems like something that litricure pieces of art usually have as ending.. first time in the plot. I mean the Sasuke-Naruto deal seems to be closed (except if he gets away), now all of the epic characters were 're-shown', all the tailed beasts.... what else....
Anyways, the only thing that would make me think it will last lenger is that Tsunade said Naruto still has a lot to develop to become Hokage, but he probably will get the title once.
That's supposed to be the end.. right? Sasuke deal closed, peace, and Naruto as Hokage. The main plot of the whole story.