I thought they dragged a few guys there out of a sense of loyalty rather than a good mix of players who would get experience for the next WC. I.e. Taylor Twellman from the Revs, etc. But....
The thing about S. Africa is that despite the official designation and assurances from that country's leaders, there is some uneasiness that the country does/will not have the necessary infrastructure in place. Stadiums, communication, transportation, etc.... There are some who believe there should be a contingency plan to hold the WC in the US (which is probably the most able to accomodate it on short notice).