According to volume 23 of Otona Anime magazine,  Director Shinbo Akiyuki has announced that current anime, Nisemonogatari is 11 episode long.

He further added that it would be best to include the characters’ high-tempo, back-and-forth conversations and maintain the balance of the story to the very end. Shinbo also said that he want to animate the other 10 Monogatari novels by NisiOinin.