With the recent manga issue, tobi says he got his eye at the same bridge that Obito got crushed and where kakashi got his sharingan.
What do you guys think? Is Tobi Obito?
Also look at the names, They have the same letters but Obito has 1 extra O.
Obito thought of himself as weak and 'the black sheep of the Uchiha.' That might be why he didn't return to the village if he survived.
Also, maybe his eye is all that survived of his right side. Maybe his right side is Zetsu. It shows in the Manga that his right arm is detachable when he was fighting Fu and his arm became infected.
I think it is highly likely
EDIT: Also would explain why Tobi and Kakashi's eye jutsu use the same dimension