I would watch it, but wouldn't expect anything else than a UD from GSP, via much superior wrestling. Also, is Cerrone really that much better than GSP in the ground? GSP is a BJJ blackbelt and trained with some some of the best in the World. Fucking John Danaher is his coach.
As for striking, I also disagree. Cerrone is a BEAST, and I don't want to disminish anything from him. But GSP is the master of distance, timing and deception. He can also hide a takedown in a kick or a jab. About the jab: his jab is one of the best in the game too. He could stop Cerrone right in his track with it.
Cerrone wouldn't be as agressive because he would fear the takedown, like so many before him, and like all the others, he would go down. Then, GSP would work his way to half gard and just pummel him.
I love Cowboy, he's a badass, and I think he could surprise us against Ferguson. But GSP is just one of the best of all time.