As noted earlier, PWinsider reported that there was talk that Cowboys Stadium in Arlington, TX (outside of Dallas) may host WrestleMania 29.
I had reported back in November after speaking to an official at Cowboys Stadium that a deal was close for bringing WrestleMania 29 to the venue. According to the official, talks between the stadium and WWE had been ongoing and it was "a matter of when -- not if -- the agreement is finalized" and documents are signed.
Jeff Mosier of the Dallas News refuted my report, stating that it would be "impossible" for the arena to host WrestleMania 29 since the stadium will host the NCAA basketball South Regionals on March 29th and March 31st in 2013.
In e-mails I exchanged with Mosier, he stated that he heard that the stadium wasn't pursuing WrestleMania 29 because of how long it would take to build additional seating for one event, tear it down and build more seating for the other as the build out for a basketball arena would be significant in a venue as large as Cowboys Stadium.
As of now, no official date has been announced for WrestleMania 29, so the event may take in mid-March as it has in the past, making it possible to build seating for 'Mania and then tear it down for the basketball tournament.
We should officially know the location soon as WWE typically likes to announce the venue for the next year's WrestleMania a year in advance.