It's just common sense:
The Juubi saw Rikudou in Naruto and was very angry, now if Madara is the end-all of the Manga then this obscure plot point would be shafted, which is terrible from a writer's perspective.
Anyways, Kishimoto already hinted back in November '13 that Juubi will play a prominent role once more:
If Madara is being highlighted atm then logically it's either Juubi or Sasuke who will be highlighted next."The battle of Naruto and his comrades is in it’s final phase, in the truest sense of the term. About the Ten Tails, about Madara, and then, about Sasuke…I will continue to raise the tension without restraint, in every way I can! Please follow this story of a boy named Naruto a little while longer, I will greatly appreciate it." - Masashi Kishimoto, Sakiyomi Jan BANG