I see Cain employing the same strategy as the JDS fight HOWEVER, there are 2 weapons that Overeem possesses that could give Cain trouble. One of them as mentioned before are the knees, the other one which I think people are forgetting about is Overeem's NASTY guillotine.
If Cain spams takedowns he might very well get caught in a guillotine or get ko'd by a knee, though after the 2nd round, I think Overeem would be too gassed to pull off anything.
And that may be the factor in this fight. Cain only had to nullify JDS's boxing, with Overeem his facing a wide arsenal of knees and kicks. Either Overeem finishes this or he'll get finished. All up to him imo.