Top 10 in new Fortune 500 offer clues to surviving the recession

The newest list of the Fortune 500 was released today, and the configuration of the top ten companies provides some insight into how U.S. businesses may need to operate to be successful during the current recession and over the next few years.

With earnings for the list of the nation's largest corporations down 85 percent from their 2008 numbers due to the recession -- profits for the 500 fell from $645.2 billion in 2007 to $98.9 billion for 2008 -- what is it about these companies that places them at the top of the heap when times are particularly tough?