Who do toi think Tobi really is and why?

Either Shizui ou Madara Uchiha, but I think he's Shizui because he could of faked his own death.

Madara Uchiha. (Spoilers,maybe.) During the battle with Danzo,"Tobi" told Danzo to give him,Shishi's eye. (i think i spelled his name wrong..) Tobi,also told Sasuke,that he was Madara. Oh,and well..(more spoilers.) Madara,sort of i think helped itachi kill the entire Uchiha clan. (Not including,Sasuke and Madara.) But,i think its Madara. He,also told the six kages that he is Madara. So,yeah.

I think Tobi is is Obito, becuz to me the names are so similar. Tobi......Obito. I mean u can spell Tobi out of Obito with a left over "O". And that boulder probably didn't kill Obito, he probably survived some how.

It has to be Obitobecause their hair looks almost the same. He gave one his eyes to Kakashi. Tobi had one hole on his mask.

tobi is actually madara uchiha from the elder days.somehow he's not aged for many years but he is way older than the third hokage.he wears a mask
to hide his true identity from the world.only pein and konan know of his true identity.later zetsu and kisame get in on the secret

iazuna ou jst madara

he is Madara Uchiha for sure..
bcoz he appears at the first time releasing the kuoby out of koshena "naruto's mother"
and he can't be obito for this reason coz obito is too young that time..
the seconde thing is that his sharengan techniques are so brilliant and effective which not anyone even sasuke himself can have now..
and finally toi must notice the age and the wise that he had..
so definitely he is not obito and Yes he is
Uchiha Madara baby..

Before I watched shippuden
I all ready came to the conclusion
That tobi was obito because
toi see how the names are
Tobi And obito?