With the world cup just six months away, The Guardian has put together a great set of charts comparing the relative schedules of each qualifying team, based on their opponents' FIFA rankings. As you can see above, by this measure the U.S. has the third-hardest schedule, just behind Ghana and Australia. In fact, with England at tenth, Cameroon at 11th, and Nigeria at 17th, it's looking to be a pretty rough World Cup for all the English-speaking countries of the world.
Based on the these rankings, The Guardian found that the U.S.'s Group G—not Group B, as some have argued—wins the title of "Group of Death," although Group B holds the title for single strongest match (Spain-Netherlands, ranked 1st and 9th respectively). The weakest match belongs to Group F, where Iran (ranked 45th) will take on Nigeria (36th). The charts for the USMNT's and Australia's games are below, but The Guardian has complete strength breakdowns for each game and each group; you should go check them out.
It's important to remember that the FIFA Rankings, which are based on a limited number of international matches played by each team before the Cup, can differ from other ranking models somewhat dramatically. For example, Nate Silver's SPI ranking puts Portugal at just 15th, while FIFA puts them fifth. If SPI is more accurately gauging Portugal's strength, that could make a world of difference for the USMNT, although it's not like the opposition gets any easier in the knockout stage.