You mean a match of 10 games?
My vote is Carlsen, with a minimum score of 8.5-1.5.
In my opinion, Capablanca is the greatest natural chess genius who ever lived ... but Carlsen isn't too far behind, from what I've read. And Carlsen simply has far, far too much "book" on his side. He'd have won the match before Capablanca caught up with the new opening theories that have been developed since his days.
What if Capablanca had access to all the book Carlsen did? I'd still pick Carlsen as the huge favorite, because by most accounts Capablanca was somewhat lazy when it came to study. So just because Capablanca had access to the knowledge doesn't mean he would have studied it as dilligently as Carlsen has. I'd say the score would be 7-3, maybe, in Clsen's favor.
Just my opinion. I'm sure others would differ! :)
traditional chess of course