I don't think this is much of a surprise and I think Admiral M might have mentioned this when Brock returned...but looks like the plans are indeed for Undertaker to face Brock at 29 next spring. Here's a link with the clip of 'Taker asking Brock "You wanna do this?".
There's also word that Tensei has failed to impress officials (not to mention fans) and maybe repackaged yet again.
I'm still hoping Undertaker retires. He's done his time, he's already a hall of famer, and he's getting up there in Age. I thought the whole thing with HHH was a nice bookend to his career and for him to have another match at Wrestlmania might take away that meaning from this last match. He really has nothing more to prove.