Things are looking very interesting now. Since Spain will enter Davis Cup with a talented but still weaker cast (probably Almagro and Verdasco as their representatives), Switzerland's side of the draw looks more optimistic.
Federer and Wawrinka's first test is U.S.A.
Their main opponents here are Fish, Roddick, and the Bryan brothers. I don't know if they can defeat the Bryan brothers again even if they come up with an alternative doubles squad. So U.S. gets the advantage there. Federer will get his singles against Fish/Roddick (NID). From here, Wawrinka just has to win one of his matches against Fish or Roddick. He could potentially lose to Fish, but I doubt his all around game would falter to Roddick as we saw him dismantle him at the U.S. Open.
Against France. Things get very difficult here. The French will probably take the doubles. Then pressure on Federer to win both singles. The French can arguably go with Tsonga and Simon against Federer. Then Tsonga and Monfils against Wawrinka to try and get the best out of it.
If the Swiss miraculously survive this, a potential Spain, Kazakhstan, Russia, or Austria, should be simple and a relief before the finals.
Then in the finals they'd get the option of either Serbia or Argentina. I would assume Serbia would come out on top in that affair.
Then There can be a Switzerland-Serbia final and that would be quite an affair
So a slight possibility of Federer facing Djokovic at DC, at the Olympics, and at the slams, in a single year if he decides to take all the tournaments seriously.