In the video they acknowledge the contrast in love & hate for Cena (finally). Cena says it doesn't effect him, he understands why people are complacent with him but he's just him and he'll "never change". Instantly it makes me think at mania' Cena will not turn heel BUT will change his character. Maybe more serious/aggression. Then the video turns into all about how good Cena is and I was thinking "sigh they really want people to love this guy" but the ending made me think, Cena says "The match against The Rock at wrestlemania means everything... [then cuts to more Cena stuff,t hen back to Cena about 30 seconds later] .. everything" Now hang on there, that extra emphasis could swing in favour for the biggest heel turn in WWE history. Are they brave enough to do it? Now this is WWE, so you can't rule out the option of Cena turning up in Miami, beating Rock clean and rising above hate.