Toriyama claimed to have planned out DB until Goku became an old man. But he became burnt out around the Frieza saga and wanted to quit. His editor convinced him not to continue for a while longer. After that he churned out two more sagas over the next few years. It's ironic because in most interviews he seems like he's sick of talking about it, but it's popularity is so huge that he has a strong international fan base, even though it's been over a decade since he wrote the final chapter. Let's see if Naruto can make that claim in fifteen years.
But I have to agree with Dirt Monkey. Kishi always sucked with pacing, so him speeding up in his writing is a vast improvement. It sometimes took him 3 chapters to write out something that would only last a minute in real time. Hopefully he can wrap up the Pein fight in ten chapters or less.
But i don't think he's planning to end it anytime soon. What it looks like he's planning to do is another time skip. When Naruto III starts up we'll probably see a newly rebuild village, a slightly older cast (maybe Naruto in his early 20's), and Saskue as the main villain till the next time skip. I really think Kishi is planning to be like DB with the time skips. The entire series will be about Naruto's life from when he was a kid till he becomes an old man. And all the other characters will have there five minutes of glory at different intervals of the time skips. For example, maybe Naruto will date Sakura in his early twenties. Then he'll date Hinata in his late twenties after some event where she finally opens up to him. The in his thirties he marries some yet to be introduced character. Unfortunately since Kishi is such a slow writer it's taking him years to progress the story. And it'll take him decades to wrap up all lose ends.