Allegedly, yes. Eric Gargiulo of Camel Clutch Blog is reporting that the wheels are in motion for Shaquille to return to the WWE ring to take on Big Show. You may remember that Shaq and Show got into it when O'Neal was guest host on RAW. Before that, Shaq appeared in WCW to support the Hulkster back in his red and yellow days. Shaq's got good charisma and I would have no issue seeing him in the ring at WrestleMania.
Here's the physical confrontation between Shaq and Show on RAW.
Great picture from With Leather below as well.
Upload Credit: LeBronIsTheRealKing
Photo Credit: WithLeather.com