Orton turning heel because of losing a nothing match against the Big Show? Don't think so.
This isn't a sign that Orton is going heel at all. It's much like Sheamus being on the poster of Extreme Rules - it doesn't mean anything, just a guy they threw on the poster of the PPV. Same with Orton here. Him and his Viper persona are a good choice to yell about payback and vengeance being a bitch and stuff.