If Madara was Obito then wouldn't the container that he is using be younger?
When he took off his mask to reveal himself to Sasuke you could clearly see the wrinkles on his face, Obito would be around Kakashi's age.
Obito was crushed by quite a large amount of rocks. Scars can actually take the shape of wrinkles or maybe the rocks messed up his face.
Here's a guess: Mabye Tobi is Madara's son! Haha, bit of a stretch, but I like it.
Tobi was very shocked to see what was in the coffin. Maybe because it is the true Madara.
As to how he "survived" the fight with the shodaime and was never the same again.
Maybe Tobi came and took his father's eyes? Ahah.
Madara isn't supposed to be dead, but maybe Kabuto had a hunch and resurrected Madara and was right?!
How is Madara even still alive without dying from old age? A special jutsu?
If madara had a son, how old would he be?
Don't take what I say serious. But now I wonder.
I've never thought of that. But I like it.