American Express, by most American standards, a well regarded financial company, "decided" to borrow more money, in the form of issuing bonds.
This is a routine exercise by most companies, living in debt. However, typically bond yields (interest) are low, since American Express is normally a low-risk company to lend to.
However, the bonds are at "7.3 percent notes due in 2013 priced to yield 425 basis points more than Treasuries of similar maturity, according to data compiled by Bloomberg. That's 15 basis points away from the average spread on bonds rated Baa3, the lowest investment-grade rating, according to Merrill Lynch & Co. index data".
This may not seem significant to the average person, but what if, your mortgage was suddenly raised to 4% higher? What if all your friends and neighbors had this occur? Borrowing costs by companies to do "business" is as significant as your mortgage ratcheting up.
This potentially indicates that ratings of financial companies cannot be trusted, and everyone is now suspect of being junk bond dealers. And therefore "highly trusted and rated companies" will pay "junk bond prices". Until the accounting is fixed, and "level 3 assets" (assets are completely illiquid and nearly impossible to price.) are removed (open market valued), this will continue to spiral downward.
One of the USA's strength was open and honest accounting (most of the time), now we have systematic hiding of debt yielding lost of trust.