At first I thought that he was Madara but that he took Obito's body. If you look back you notice that only HALF of Obito's body was crushed. With Madara's chakra isn't it possible to heal the other half of his body?
If you look closely, when Tobi takes off a bit of his mask, and shows like 1/4 of his face you notice a strap that looks like it leads to an eye patch on the eye that is covered. That is also the eye that Obito gave to Kakashi.
But sadly if Madara was indeed using Obito's body then his body should be as old as Kakashi which doesn't explain why his face looks kind of old.
~The Good Boy~ The OFFICIAL Tobi fanguild! [Naruto]
