Perhaps I "missed" it. But I saw similar rebuttal and took it upon myself to watch that exchange, in it's entirety, several times...with the volume as loud as possible to hear these "shushes" and "hisses". I can't seem to hear anything. I know dam sure you can hear groans and hisses from the audience/members during a Congressional House speech.
So either either those were the nicest and shyest hisses and shushes ever, which contradicts (as is being touted) that a rather large portion of the audience were angered and dismayed at the boos...that they quickly responded with the shushes...
...or, perhaps the level of angst to the boos was not as large as is being stated or...non-existent.
I got into an interesting back and forth with lilMike's blogger friend on twitter today. Seems like her claim has been met with quite a few guffaws and a few hundred tweets in support of my claim vs one for her scientific theory.
It's funny how the right will resort to science to blame all of this on a concrete floor, yet denies global warming and claims the universe was created 6000 years ago by a friendly guy with a long beard.