While a lot of people are arguing about who won the two promo exchanges that we have seen between Rock and Cena in the last two weeks, I just have two words to say for what I feel about these exchanges. Not Fair.
TWJC is right when he says that the fans of one party aren't giving the other an inch, but so aren't the wrestlers themselves. Yes, I get that Cena and Rock are quite different as wrestlers. Rock is a comedian while Cena is the more serious character. But that does not mean that they should completely no sell the other guy's promo.
What Cena has implied throughout this whole promo war is that Rock's promos are immature and this week he even said that Rock is nothing without his catchphrases. Well, this might resonate with some of his fans but John, you aren't really telling us anything earth shattering. Rock's promos, regardless of the amount of substance in them, will continue to get cheered.
In my view, it is Cena who should come down to Rock's level( forgive me for not coming up with a better expression) and talk in his language. Yes, I believe he should try and go insult for insult against Rock because this feud is about John Cena proving once and for all that he is better than Rock. Pointing out the immaturity of Rock's catchphrases isn't going to cut the ice because everyone knows it and most people still enjoy a Rock promo despite that.
The question that some of you must be asking after reading this is, why should Cena change his style? Why shouldn't Rock try and come up with a more "mature" promo? Well, the reason is simple. Rock, due to the simple reason that he came before Cena, is the legendary performer here and Cena is the superstar of today who has to measure up in front of the legend. It is like Rock/Hogan with Rock having taken Hogan's place in the feud. Look at the promo in which Rock challenged Hogan to a match at Mania 18. The guy who cannot go a sentence without uttering a childish insult was actually respectful towards the man. Because that has been the way Hogan has operated. When you talk about beating Hogan you do so by talking by talking about the stuff he was good at and what he stood for. Stuff like honor and passion. When you talk to The Rock, try and counter his insults with some better insults.
In a way this is like the feud between HBK and Hogan. HBK tried to belittle Hogan by saying that he gave the best match of the night every night he wrestled. Again, a statement that revebrated with a lot of his fans but conveniently dodges the more relevant fact that Hogan was a much bigger draw than him. Cena calling out the immaturity of Rock's catchphrases to belittle him is an irrelavant fact just like HBK saying that he gave a match of the night performance every night. The relevant fact is that Rock's catchphrases have worked and still work.
That is why I have high hopes from the segment that will take place next week with Cena rapping because that is where I feel they talk on a level playing field. I also hope that for once Cena speaks first and Rock gets a chance to counter Cena's arguements because it has been the other way so far and a reason why Cena is looking better in these exchanges. So far he has had the opportunity to use Rock's catchphrases against him. Why shouldn't Rock get that chance too?
This is my favorite post out of anyone who has disagreed with my opinion so far. Seems like a very well thought-out opinion that has taken the time to listen and understand where both Cena fans and Rock fans are coming from.
Before I start, I'd like to let you know that my response probably won't be as long as your post (unless I get absurdly caught up in the moment and start monologuing, in which case I'll apologize for the opposite reason). Let me try to sum up your ideas into a couple of pointers and give my opinion on them. I'll try not to miss anything.
1) Cena shouldn't no-sell The Rock on the mic.
I think it's perfectly in character for this feud for Cena to no-sell The Rock. The way I see it, Cena has taken up the role of representing people like me, who don't really like The Rock's style of promos. If someone came at me like The Rock does at Cena, I'd respond similarly to how Cena has been. I support it, because it personally appeals to me. Now, saying that, I'd also like to point out that I thought Cena was splendid against The Rock early in the promo when he rapped about him. However, I like this turn of events even more.
2) We already know that The Rock's promos are immature; Cena isn't bringing anything new to the table by saying that.
I don't think anyone has ever pointed it out the way Cena is right now. It might be acknowledged between some of the fans, but I'd even point to this thread in showing that there are a fair number of fans who don't see it that way. I'm fairly certain that no one would call it "mature", but some would probably disagree if I called it childish. Basically, I think Cena is, in a sense, bringing something new to the table, since I don't recall anyone else making a point of it at any point in the past on the mic. Yes, people will still like The Rock regardless, and that's totally fine. However, I feel that finally someone in the ring is voicing my opinion.
3) Cena should change his style to match The Rock's out of respect, like The Rock did for Hogan
When Cena challenged The Rock to the match, he was as respectful as The Rock was when he challenged Hogan (I looked up both challenges on youtube to make sure I wasn't being a total jackass). Aside from that, The Rock kayfabe mocked and disrespected Hogan plenty before their match. He stayed with his own character and didn't change for Hogan on the mic, just as Cena is doing for The Rock. One major difference between the two that your argument doesn't mention is that Rock/Hogan wasn't decided too long in advance, so the build didn't have time to become "personal" like it has between The Rock and Cena.
4) Cena has always gotten the last word, and The Rock hasn't had the chance to use Cena's catchphrases back at him.
Two weeks ago, The Rock got the last word against Cena, and it just didn't work out too well. The Rock made fun of Cena's catch phrases earlier in the feud. It just doesn't resonate as much anymore in my opinion, since we rarely hear Cena using them himself. Cena hasn't really relied on his catchphrases for a few years now, since he uses them very sporadically nowadays. I actually think his opponents in feuds have used it more than he has at least in this last year.
I'm looking forward to next week's segment, too. I was always a fan of The Rock's diss songs (although I only remember him doing them as a heel), and Cena's diss raps are always a pleasure. I'd prefer that Cena stick to the same shtick as he has been the last few weeks, since like I mentioned, that speaks more for me than his rapping, but if he's going to go into full-insult mode, this is how I prefer he do it.
So yeah.. Sorry that I dragged this out more than I originally intended. I stand by opinion that you have the most legitimate complaints out of anyone who has posted in this thread negatively about the way Cena has conducted himself in the feud, and as I was writing my response, I felt you would prefer a decent description of why someone might feel otherwise rather than a "omg no, you are just a biased rock lover" response (although I do intend to use that line the next time "I Hate Cena" or maybe "HollywoodRocksomethingsomething" posts something in here).
). In real, both knows how much they mean to fans and WWE. We can't say for sure how they treat each other outside the ring, but both of them are doing a real fine job in sticking to their character. 
I understand your point of view & for the most part agree.