From BloodyElbow.com:
Rashad Evans will definitely fight Forrest Griffin for the light heavyweight title, but it may not be at UFC 92. Sources indicate to Bloody Elbow that the UFC is considering moving that fight to another show. There is some internal concern that with Brock Lesnar vs. Randy Couture headlining in Vegas in November, and GSP vs. BJ Penn headlining in Vegas in January, Vegas fans may skip the December show if it doesn’t have a huge name on it.
There is still an outside possibility that Chuck Liddell could fight in December. He is an established draw in Vegas, and he does not plan to retire after his last loss. There are numerous potential opponents he could fight in December as well, including the returning Mauricio “Shogun” Rua. He was originally scheduled to fight on that show as well, but it’s unclear whether he would be ready to fight again after such a bad knockout.