Both players are dominating the rest of the ATP. Nadal is unbeatable on clay and Fed is unbeatable on grass and probably most hardcourts. So lets say you are watching a match that you know Nadal or Federer will almost certainly win. Which match is more interesting? It seems like people here say that watching Nadal is more exciting because Fed always wins. But now Nadal always wins on clay so that argument no longer works! Most of Nadal's matches are not that exciting. Lets say he is playing Robredo on clay or Ferrero on any surface. You know that Nadal will win for sure. And after watching few of his great passing shots or his amazing defence gets it eventually starts to looks all the same. He just gets everything back and eventually the opponent makes the mistake. Sure some of his passing shots look unbelievable. But after seeing several of them it becomes repetitive. So how exactly are we supposed to be excited about seeing Nadal play? On the other hand lets say Fed is playing one of his beeyatches. Lets say Ljubicic. Sure I know Fed will win and maybe even in straight sets. But at least I get to enjoy beautiful tennis that has more than just great defence and occasional passing shots. To me watching awesome winners is way more exciting than waiting for frustrated Nadal opponents to make a mistake.