From pwtorch.com:
The Torch has learned that the top three matches for WrestleMania are slated to be as follows:
-Chris Jericho vs. Triple H for the WWF Hvt. Title
-The Rock vs. Hulk Hogan
-Steve Austin vs. Scott Hall
There is also talk of a match involving Kevin Nash and Undertaker, although since both are heels, that may be switched around. There is also talk of Nash & X-Pac vs. Undertaker & Kane, or other tag combinations.
The undercard, as usual, won't be a priority until after Sunday's No Way Out PPV.
There is definite talk of Eric Bischoff being involved in the NWO angle very early on, and it's considered a virtual lock he'll be involved in it at some point within the next few months.