It doesn't really help that the title itself spoiled chapter 651...
OT: I don't think so. Maybe did some damage, but I highly doubt he's dead. I just wish next chapter isn't some prolonged battle strategy of how they're going to beat him if he did survive and him saying "It's impossible."
I love this manga, and I think it's perfect, but almost every Naruto v Obito scene in the manga has been:
Naruto: I'm going to beat you with a new feat
Obito: It's impossible
Naruto: *does feat*
Obito: Agh.... Nope. Impossible
Naruto: Well.... I'll think of another new feat. *does new feat*
Obito: Agh.... Nope. Still impossible.
And repeat. Please let this not happen again.