Junior for me I think Cain won't want to stand with wen he feel the power and speed of jdss punching! Ny 1 think different ? 
Been thinking about this a lot lately...At first, I thought Junior, but now I'm gonna be putting my money on Cain. They're both very fast HW's, but I think Cain may have a slight speed advantage, and he obviously has the cardio advantage. JDS may have the better chin(don't think I've even seen him fazed by a shot yet), but Cain's diverse striking and chain wrestling is going to wear JDS down, and Cain will probably TKO him for the win in the 3rd or 4th round after JDS gasses.
Probably the most excited I've ever been for a heavyweight fight(Wasn't watching MMA when Fedor/Cro Cop happened, and I feel this is closest we'll get to seeing a fight similar to that anytime soon in terms of skill level + styles)
I got JDS in this one. Cain is a beast but I don't know how the layoff after the surgery will affect him.
Cain. Junior is definitely one of the greatest HW's of all time and I have no doubt that eventually he'll be champion, but IMO Cain is the better all around fighter. I know Cain's been out for a minute, but he hasn't been sitting on his ass, and I don't think cage rust will be too big of a factor. I see it being a war though, can't wait. Contemplating making the trip up to San Jose for this one
If Cain wasn't coming off a layoff I'd pick him confidently. But I still think he'll win. The first guy nailed it with striking/wrestling combo being the difference maker. Wrestlers (with good takedowns/shots) who can strike well are gonna rule MMA for awhile I think.
Damn good fight. Probably take Cain but it's kind of a toss-up.
Kind of a shame one has to lose. I like both and think they are the clear cut best HW's out there.
Cain is one of the only guys that im confident about betting on even after hes coming off an injury. Insanely hard worker, i dont think he will ever come into a fight not prepared
Junior, the layoff is gonna hurt Cain and he needs to be on top of his game to have a chance against JDS. I have been waiting for this fight for a long time I can't wait.
Cain-diverse striking and beast wrestling will win this one.
Although jds could easily win as well, biased Cain fan I guess, both are badass.
I think if jds can keep it standing he will win. but if Cain can get it to the ground it will be cains
Cain has better overall striking, head movement, wrestling, endurance, etc.
This = Remaining champ.
Cain in a mauling
discodrew - I think if jds can keep it standing he will win. but if Cain can get it to the ground it will be cains <img src="/images/phone/post_tag.png" alt="Phone Post" border="0" style="vertical-align:middle;"/>
Obvious?
Cain ALL DAY...
JDS doesn't have the cardio to compete with Cain for 25 minutes. He didn't go full force for 3 rounds against Roy or Shane Carwin. You could see him pacing himself considerably and IMO should have finished both of those guys. If he's holding back in 3 rounds fights he's dominating he will have trouble with Cain's pace.
Also, Cain's striking is sick. He mixes punches and kicks very well and JDS is primarily a boxer. Obviously Cain has WAY better wrestling and IMO better overall transitions.
Anything can happen, but Cain can seriously burn JDS with his pace and finish him.
JDS is a scary beast of a boxer, but Cain comes from that die first wrestler mentality (ring rust issues not a big issue I don't think), and his striking is top notch at this point. Holy shite what a fight. 5 rounds? No way. JDS. TKO 3rd round.
Anyone who says one or the other with confidence isn't doing his homework.
This is a coin toss. I believe Cain is the best fighter in the world, but Junior is one guy who seems to be made to beat Cain (good TDD, great scrambles, great hands, speed/quickness, durability)
JDS has a mean streak and is all bizness. And skills that go far beyond one punch knockout power (though he's got that going on too) to back it up. Cain is well rounded at superstar level. Agree with previous poster...anyone saying either all day is nuts. Jon Jones vs. Rampage? All day minus the "happens every Saturday" knockout? Probably. JDS and Cain? Pick em.
ttt
Cain by explosion 1st Rd
Cain but it will probably be a decision.