Dean Baker on Standard and Poor's rating agency, who downgraded* the United States' government's outlook to negative.

It is also worth noting that S&P has a horrible track record for judging credit worthiness. It rated hundreds of billions of dollars of subprime backed securities as investment grade. It also gave Lehman, Bear Stearns, and Enron top ratings right up until their collapse. Furthermore, no one was publicly fired for these extraordinary failures. Investors are aware that S&P's judgement does not mean very much.

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* the US still has a AAA rating, but S&P now says the outlook is negative, or not good. They did this to Japan, but nothing ever came of it and the market allowed the Japanese government to continue to borrow at low rates.