CM Punk is back to what made him great. Late on Monday Night Raw, Punk shocked the entire WWE universe by turning heel and attacking The Rock. This is played out in order to set up a feud between the two wrestlers for Summerslam.
This is going to be quite the interesting feud. For it to work, CM Punk had to turn heel. He could not be a face against Rock and this way makes a lot more sense. Punk is a lot better as a heel and it should help him get a great reaction. His character was never meant to be a face. It just does not work.
As a heel, there are a lot of options. Punk can go back to his old persona. The new fan pleasing CM Punk was just not a good character. It simply did not work. Punk could never be a face at the same time that John Cena is. It just does not work. This way, a Punk/Cena feud can be revisited down the line.
The company promised the fans a lot for the 1000th episode of Raw. They certainly gave the fans a lot more than they expected. This was the perfect ending to the show and it swerved a lot of people. No one expected CM Punk to leave Raw as a heel.
The best part about this is that the feud is not repeated. If the company tried to do a Punk/Rock feud based on mutual respect, that would just not work. This way sets up a way for a great payoff at the next PPV.