There is something i thought about.
How did Tobi achive the MS Sharingan? If he is not Obito this should not be possbile for an transplanted eye. Danzous already had Ms ability before transplant, and Kakashi seems to be connected with tobis~
But this is not everthing i thought about. If Tobi could activate MS abilities in Sharingans, why didnt he done it to the other dozen one he got hidden? I mean he could have found so many strong MS abilities to use for battles, and maybe even a better one then his own. But as we saw at Fight with Konan he hid his other Sharingan wich for sure was a reason to say it is an transplant.
Wont this mean that his right Sharingan is his own eye which would mean, that Tobis Body also has to be Obitos Body or Obito himself?!
Based on the last manga chapter, it would seem that Tobi is Obito. However, there are a few outstanding items that need to be addressed to explain how Obito came into posession of the Rinnegan and Mag. Shargingan, etc. My theory is that Obito was able to survive the cave in (not sure how at this point), but perhaps the cave-in uncovered Madara's body. Madara's body could provide Obito the 1) Mag. Sharingan 2) Rinnegan and 3) the First Hokage's cells, all of which he does possess and had used at least 16 years earlier.
1) Mag. Sharingan - he controlled the nine tailed fox and 3rd Miz Kage, well before he could have mastered the Mag. Sharingan
2) According to Tobi, he gave Negato the rinnegan. As we came to find out later, Madara possessed the rinnegan. Also, Tobi was able to read all of the text at the hidden room known only be the Uchiha clan. This was where he deciphered the text regarding the 10 tails, etc.
3) Obito has been able to regenerate his arms. He lost his left arm twice, once to 4th hokage and also to Danzo's henchmen, and he didn't seem to care all that much. The "goo" arm hints that he can regenerate to some extent, and that leads to the 1st's cells. ToHe also has that large tree that resembles the 1st Hokage.
4). In addition, Tobi was scared after he saw Madara in the Edo Tensei coffin by Kabuto, and he asked "Where did you get that?".
5) The nine tailed fox recognizes the chakra from Tobi is the same as Madaras.