The Deadman will never lose at WrestleMania. He survived Sweet Chin Music three times in this much. THREE times! Even Ric Flair with his entire career on the line couldn't withstand three SCMs. But Undertaker could, because he is absolutely, undeniably, incontrovertibly unbeatable at WrestleMania.
shareIt seems inevitable now that the only person that has been built up as a real threat to The Streak would be Cena. Personally, I don't think Cena would agree to break it, even if the WWE writers wanted it.
If it is indeed Cena/Taker at WM27, I would mark out like a little kid if 'Taker made him tap.
I agree that a match between Undertaker and Cena at WrestleMania is inevitable. However, I do not think that that match will occur at WrestleMania 27. Undertaker will face someone else at WrestleMania next year (thus becoming 19-0) so that the feud for him and Cena going into WrestleMania 28 in 2012 will be about Cena being the only person who could possibly end the streak before Taker reaches the "impossible" 20-0.
Now, if I was part of WWE management, I would not make the match a normal singles match. Imagine this: The Undertaker vs. John Cena at WrestleMania 28 in an "I Quit" match. This would be an amazing stipulation and storyline that would draw in millions of viewers: Undertaker is seemingly unbeatable at WrestleMania, so what could possibly make him give up? On the flip side, Cena is undefeated in "I Quit" matches, as he pledges to his "Cenation" that he'll never quit.
That match would seem like two universes colliding. This is how I would book the ending: Cena locks on the STF and refuses to release the hold. The Deadman refuses to give up, but starts to fade. It appears as if the Lord of Darkness may be fading! Suddenly, Undertaker springs back to life and manages to reverse the STF into Hell's Gates. Cena struggles to free himself, but he can't. However, keeping to his promise, Cena refuses to give up. In an homage to Austin vs. Bret at WrestleMania 13, Cena passes out. Due to the fact that the match can no longer continue, the Undertaker wins via default. This way Undertaker becomes 20-0 and Cena can retain his credibility by never having uttered the words "I Quit" (though his "I Quit" match record would technically be marred with a '1' added to the loss column).
Afterward, Cena would snap out of his unconsciousness and Undertaker and Cena would shake hands.