While there are no indications it could serve as the main or co-main event for UFC 140, the fight card just added the most significant fight to date. Namely, Frank Mir and Antonio Minotauro Nogueira will rematch one another in Toronto. From the UFC's website:
A heavyweight standoff between two big names has been booked for December, as former UFC heavyweight champions Minotauro Nogueira and Frank Mir have verbally agreed to rematch at UFC 140 in Toronto.
"Both men are known as two of the premiere submission specialists in the division but have shown dangerous striking skills as well," said UFC president Dana White.
Mir and Nogueira previously faced each other at UFC 92 in December of 2008. Mir won that bout by second round TKO (referee stoppage). Nogueira and his camp, however, argue he fought Mir while recovering from a staph infection in addition to dealing with possible knee issues.