Treasuries have rallied now... lol market basically telling S&P to f*** off.
As the saying goes, "Don't fight the Fed." S&P is basically saying what everyone has known for a long time, but don't underestimate the significance of the fact that it is being said at all this way. The effect may not have been reflected in today's price action, but Helicopter Ben won't always be on station to put a bid under every Treasury ever issued.
They're now monetizing about half of the PD takedown a week after every auction...with the PD's flipping them at a profit, of course. That is a staggering amount of debt. For comparison's sake, consider that the "$38 billion" in Federal budget cuts that recently got so many headlines (which in the end turns out to be more like $350 million, and is actually -$3.3 billion if you count "emergency spending," but let's at least keep the Kool Aid in our mouths for a moment) is about what the Fed POMO'ed in the last two weeks alone.
The current "There Be Dragons" is still what happens once QE ends--or if it does. As June approaches, and Congress does nothing (except raise the debt ceiling, of course--we're within about $50 billion of hitting it right now), yields could get pretty interesting.
As for the "unsolicited" thing...ECB stopped supplying data shortly before the US did, so EUR sovereign issue ratings are unsolicited as well. Frankly, I've never known what to make of this, and it caused barely a ripple, so if there's something to read into it, I don't know what it might be.