It's certainly not set in stone just yet but Strikeforce Middleweight Champion Luke Rockhold is preparing as though he'll be defending his title next against Tim Kennedy.
From the above video (transcription via Bloody Elbow):
"I'm excited about the fight with Kennedy. I think he's highly underrated, very tough dude, he poses a lot of challenges. I'll be ready. It looks like it's finally going to happen.