The S&P downgrade was a farce. Almost every major bond investor, including nations looking for reserve currency, have rendered the market equivalent of a "dope slap" to the satrap at S&P who bullied his partners into using their stature to play politics.
The sell-off was a panic, more over sold than a prostitute at a sailors's convention.
Today was the correction but schizoid as evidenced by the wild gyrations. We are still down a bunch from a week ago. Likely 23-24 is a reasonable short term trading range given the general paranoia. Where it goes from there is conjecture, anyone's guess.