It will be interesting matches if Anand plays Carlsen. I think the game outcomes will not be probably all draws. Although Carlsen has higher rating than Anand, it is not sure who will win the match. One of my point of views is Anand has more experience than Carlsen. However, Carlsen is a lot younger than Anand, and he has a physical advantage in the match.
If Anand plays Carlsen...

they played each other twice in the bilbao masters. I think it was soccer scoring and Carlsen won one game and the other was a draw
I think most of the games will be draw but not like the one Anand-Boris! It will be one like Topolov-Anand one! Magnus has to play careful in most of the games as usual trick of complicated, risk-taking positions etc., won't work with Vishy as he is more experienced and balanced player. However, Magnus has age advantage!
Will the outcome be all draws by Vishy?