According to UFC.com:
UFC President Dana White announced today that former UFC heavyweight champion Brock Lesnar and number one contender Junior dos Santos will match wits as the coaches of season 13 of the hit Spike TV reality series.[UPDATES] via @Mike_Fagan_13, @ufc and @arielhelwani:
Following the season, which begins filming this month and begins airing on March 30, Lesnar and dos Santos will then match fists in the Octagon later in 2011.
Dana White: "I was in communication with Brock and his camp. The stuff about not wanting to fight, wanting to go to WWE was wrong."
Dana White: It was tough getting Lesnar to commit. I'm preparing for a tough season. It's going to be an interesting 6 weeks of filming.
No interim title at end of TUF 13 - Lesnar and Dos Santos will fight and winner gets Cain Velasquez for the belt
Lesnar vs. Dos Santos will be sometime in June. "100% in June."
Dana tells Vancouver to "keep your fingers crossed" because "you could be getting" Brock-JDS.The Ultimate Fighter 13 debut coverage