Many thing tie both Tobi and Naruto together. They both have an ability to "change people". Tobi was curious how Naruto was able to convert Nagato and wanted to see first hand the person that had caused Nagato to betray him, so he went to Naruto's inn during the Kage meeting arc to converse with him. This would have been an ideal time for Tobi to take Naruto out since only Kakashi and Yamato were there. I believe the reason he didn't is because he needed the timeline to proceed to his own creation. Another curiosity are some actions taken by Tobi. He pauses, lingers, and respectfully closes Nagato's eyes following the fight with Konan. He takes umbrance with Kabuto's suggestion that Jiraiya be resurrected telling Kabuto not to push his luck. He has knowledge of some Kakashi's catch phrases about "Acting Tough" and has firsthand knowledge of Kamui and knows that it won't work on him. Both Tobi and Minato have space/time Jutsu and Naruto will probably learn the elements of space/time jutsu as well. Tobi has used chakra chains that are identical to Naruto and Kushina. In chapter 573
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we see that Tobi was unnerved when Naruto revealed that he knew the names of the tailed beasts. He says "that face". Take a look at the panel preceeding that then compare with the Dark Naruto conflict
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. Look similar? Both of them occur when Naruto is taunting an enemy who seems to know everything about him, but he is showing they don't, and their reaction is the same. So, it appears that Tobi has faced Naruto before and that he "knows the extent of his power and what he really is"
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. This is probably because he is no longer privy to all of Naruto's knowledge. There was also Tobi's inability to phase through Naruto's head which resulted in the headbutt. I believe this occurred because Naruto had already expunged his darker self, and now it cannot exist in the same space any longer. Tobi is also another word for jump and I believe that he not only jumps from place-to-place but from body-to-body and from time-to-time. Another item that ties most of the antongonists together is the desire to recreate the abilities of the So6P. Zetsu, Danzo, Madara, Orochimaru, Pain, Tobi all seem to be either part of an experiment or an attempt to recreate the So6P abilities. It is the obsession with the So6P's body that is of interest. Let's analyze Tobi's statement. I am Nobody, I am No One. We know the Kishimoto loves word play and who is in need of a body? A recently excommunicated piece of someone's conscious. Tobi's body will probably end up being Kagami atm, but it's the consciousness inhabiting that is the real issue and that consciousness is the darker part of Naruto. When Tobi put his hand on Naruto's head his intention was to pull the other conscious out and use Rinne Tensei to re-occupy. Hence his his comment regarding Nagato that Rinne Tensei was for his use. This consciousness seems to have the ability to combine with other consciousness like other Jinchuriki, Sasuke, and tailed beasts, which I believe is a unique ability of the Jinchuriki. Finally we have Tobi's own statement that this war will make all pasts, presents and futures irrelevant. Tobi feels justified in doing anything necessary including wiping out the Uchiha clan. Why? He intends to erase the timeline anyway so none of it will have ever happened.