So let me see if I get this straight..instead of just reading the WrestleZone thread that clearly said JR Blog: UNDERTAKER/WMania...you decided to make a thread about it, really? REALLY!?
http://www.wrestlezone.com/news/242446-jr-blog-undertakerwmania-hardy-and-foley-wwe-returns
How hard was it to go back a whole...3..count them...THREE pages to find the answer to this!? If Undertaker retired everyone would know. He isn't going to bow out quietly. The man that IS essentially WrestleMania. I mean REALLY...
Just incase you are too lazy to copy/paste the link (because I mean you didn't want to bother to even look a few pages back here is the DIRECT QUOTE from JR:
"Do I think that the Undertaker will physically be able to perform at a main event level at future Wrestlemania events. Absolutely. However, if Taker is unable, for any reason not be be what he expects of himself, he will never step in the ring and be less than his best. I do not expect that to happen.
I expect to see Undertaker attempt to go 20-0 at WM28 but have no idea against who."