Everything is in place for a Cena heel turn, but I think WWE will swerve it too. Not sure how, but that's what I think. Also, I've heard that WWE have plans for Miz to be the first to cash in MITB and fail to win the title (they aren't recognizing the Kennedy one). So I think Barrett will win somehow, Cena will stay face for now, and Miz will unsuccessfully cash in (but Miz will be world champion in the near future). The part R-Truth plays will be interesting. A heel turn for him is an intriguing thought, but with his current theme and gimmick, is it possible for him to be heel? Who knows.
"The path of the righteous man is beset on all sides by the iniquities of the selfish and the tyranny of evil men. Blessed is he who, in the name of charity and good will, shepherds the weak through the valley of darkness, for he is truly his brother's keeper and the finder of lost children. And I will strike down upon thee with great vengeance and furious anger those who attempt to poison and destroy my brothers. And you will know my name is The Lord when I lay my vengeance upon thee."