Well this is My best prediction about who is Tobi; First let's see all this Information
1)Tobi hates Konoha=>Tobi is not Obito
2)Tobi was surprised when Kabuto showed him Impure world ressurection and it was not planned and when Madara was summened he was awesomed to be ressurrected with that technique =>Tobi is not madara
3)Itachi was already resseructed =>Tobi is not Itachi
4)Tobi's plan is to rule the world with MS Tsukomyu , and we all know that using MS too long makes you blind only if you are taking some body else MS and this transplent doesn't work only between Uchiha shinobi =>Tobi is an Uchiha who took his MS from another Uchiha
5)The only way that an Uchiha could get informations about 10 tails bijuu is weather he is from a very ancient time or he read it from the uchiha secret rock, and we know that Tobi needed Riingan to accomplish reading The informations from the rock => Tobi is not the sage of six paths son and this confirms that he is not tobi since tobi did not had MS or Sasuke's father
6)Tobi is using his MS and he lost one in the fight vs Konan and we saw there that he can solidify himself (He is made of Real Flesh) => Tobi is not Shisu since Shisu los both of his eyes one to Itachi and and one To Danzo and Tobi was looking for Shisu's Eye from Danzo
7)Tobi is an Uchiha who lived in the time of Hashirama and the birth of Nagato since he said that he is one who gave him Riingan=>.........................
Finally) The only shinobi who aquires all this conditions is Izuna : He has MS (Can read the rock) and lived by the time of Hashirama and not yet ressurected (not dead) and he have the reasons to hate Konoha and of course he could take Madara'eyes back since he was burried in a place even Kabuto could reach and maybe he took Hashirama's flesh from dead Madara's weapons Or Madara's eyes got mixed with Hashirama's blood or some stuff like this and His weakness was for making a technique to live all this time or for taking a dead uchiha eyes
Also I can't see that is possible for Tobi to be a new Charecter because Madara is the first one who activated MS and all the othe known mentioned Uchiha who had it are Izuna then Shisu and Itachi and Sasuke and to make a new Uchiha is Tobi this will be A crap
So can anyone beat this Analyse or find a gap in it