Ranking isn't important. Ranking is one way to get traffic. Traffic is important. If you master PPC, or Videos, or Forums, or Answers, or any of the other ways to get traffic, then you don't really need Ranking -- but it will come on it's own. Of course, once you have traffic, you need a way to turn that traffic into money. Without that, all of the ranking -- and traffic -- in the world don't mean squat.