According to The Fight Network, this bout has been added to UFC 79:
Tony DeSouza has been slated to face Roan Carneiro in a welterweight bout at Dec. 29's UFC 79 at the Mandalay Bay Events Center in Las Vegas. DeSouza (10-3) joins teammates BJ Penn and Joe Lauzon on the roster, while all three are currently preparing together at Penn's MMA Academy in Hilo, Hawaii for their contests.
Two very tough, very good grapplers. This one should be fun.