Personally I don't think Sonnen has a chance, at least on paper it looks that way to me. Jones has shown the ability to perform under pressure, and his technique is sharp. The only way I see Chael winning this is if Jones has a brain fart, and I don't see that happening.
On the feet Jones all the way, on the ground Jones all the way. He has out-wrestled pretty much everyone I don't see Sonnen being any different. Sonnen was a big MW, but as a LHW he's average sized, while JBJ is a big LHW and will have weight and length on Sonnen. On the feet there's no question.
If Sonnen does manage to get him on his back or in a scramble, I see JBJ either getting right back up, or going for submissions. He submitted Lyoto, Belfort and Rampage - all within 2 years I think. Sonnen submitted Brian Stann, and got submitted few times himself so you have to give the grappling edge to JBJ. So for him it's pick your poison.
"Let them see that their words can cut you, and you'll never be free of the mockery. If they want to give you a name, take it, make it your own. Then they can't hurt you with it anymore." - Tyrion Lannister