Source: Wrestling Observer
Reports within WWE say management wants the winner of the Royal Rumble to be an absolute shock, so don't expect to see The Undertaker, Shawn Michaels (despite the event being held in his hometown) or even Randy Orton get the nudge.
Apparently, Vince McMahon has very high regards in working on the ECW brand in making it as strong as both Raw and Smackdown. By doing so, Vince has expressed feelings of having an ECW competitor go over this Sunday. Right now, McMahon is leaning towards CM Punk, who would come off as both a shock, and a surprise. At this point, management doesn't feel anyone is as over with the crowd, with the exception of RVD, who has a very slim chance of gaining another major push in WWE anytime soon. Marcus Cor Von (Monty Brown) was brought up several times as a possible contender for the ECW Title, but many feel he isn't in any position to win the Royal Rumble match, and he is expected to have a lengthy build-up to WrestleMania.
Even with CM Punk getting the unexpected Rumble win, the ECW Title match isn't expected to go on as the main event at WrestleMania, but would more than likely be apart of a triple main event scenario. The plan right now is to have a fatal 4 way match with Lashley, Test, Cor Von, and Punk