I dont think Jones right now has the tools and skillset to be much more then a mid-high HW. I think there are a LOT of fighters north of 205 that would have a lot of success against Jones. I would say that if he were to stop cutting weight, and put on the 10 speculated pounds, he would be around the level of guys like frank mir. Good enough to stick around near the top, but definately a source of prey for guys like Cain, and JDS..
Specifically, I think Cain wins in dominant fashion over Jones, as Cain is relentless. I dont see Cain getting caught up like rampage and rashaad, watching the Jon Jones show. I think Cain puts a steady pressure on him for the entire fight, and either wins via GNP stoppage, or UD