So am I. Simply because it makes far more sense for the guy who, y'know, actually works for the company full time to come out on top.
As far as I can see, there's two arguments that people have against Cena. 1) He can't wrestle/only has 5 moves and 2) He's forced down the viewers throat.
Well, his matches against Umaga, Shawn Michaels, Jericho and JBL were all great matches, and he even managed to work with Khali and Lashley to their best matches in the WWE. His "five moves of doom" make sense because it builds the crowd up. Like with Chris Benoit, you knew that when he hit his German Suplex combo that he was going for the diving headbutt, or Shawn Michaels had the series of moves that led to the Elbow Drop followed by the Sweet Chin Music.
As for being "forced down the viewers throat," he's the most marketable man in the business right now. He's the first guy since The Rock to really cross over into other markets, with his films (which weren't great, but they were fine in terms of being daft action movies), and his album (which really really wasn't great). I was too young to watch Hulk Hogan in his heyday (only got into wrestling around '98), but I imagine he was in the main event just as much as Cena. Going back further, Bruno Sammartino held the title for years!
That's not to say I don't like Rock, far from it. He was my favourite WWF wrestler back in the Attitude Era (not my overall favourite, because that was Goldberg), and it's a nice bit of nostalgia to see him back in the ring hitting his signature moves and bringing out all the catchphrases, but that's really all it should be.
Wait, wasn't there some other guy involved in the match at 'Mania? The Muzz? Holds some sort of belt, I think.
Edit: Bloody hell, my longest post on Redcafe ends up being about wrestling. Typical.