According to The Wrestling Observer, as of this writing, the following are the top four matches currently scheduled to take place at WrestleMania 29:
-The Rock vs John Cena for the WWE Title
-Brock Lesnar vs Triple H
-CM Punk vs The Undertaker
-Randy Orton vs Sheamus for the World Title
These matches/plans can of course change at anytime, but we have been reporting over the past couple weeks that WWE has a pretty firm idea of what the top of the WrestleMania card will be, so it's likely the above four matches are a lock for the big PPV this year.