It was revealed during the UFC 108 post-fight press conference by Dana White that due to Rashad Evans' win at UFC 108 over Thiago Silva, the fight against Quinton “Rampage” Jackson is pretty much a lock.
When, you ask? White claims that the fight is likely to take place in May. He said he would try and make the fight for May 1st, which would be UFC 113 in Montreal, but said he couldn't guarantee it. The other May UFC pay-per view is UFC 114 on May 29th in Las Vegas.