This will be a relatively short diary.
A blog at the Financial Times discusses Romney's Terrible, Horrible, No Good, Very Bad Week he's had.
It then goes on to explain why this video is so awful for him:
Even with America’s relatively low voter turnout rate, Mr Romney’s first instinct to defend his words seemed reckless. Is he now committed to stick to his guns? If indeed he refuses to retract anything but his inelegant wording, we are probably in for a ruthless stretch of the campaign (having celebrated Thanksgiving early, the Obama campaign is now moving onto Christmas). Alternatively, should Mr Romney waver and then try to retract, the backlash from the right could be strong. There is also the problem of his reputation for flip-flopping.In a nutshell, he has two choices. First, he can be Mr. Etch-a-Sketch and try to paper things over with the voters he's insulted by "walking this back" somehow. His first attempt went over about as well as the Hindenburg, and doing so would just help alienate the conservatives he needs in order to win.
Whichever way you look at it, Mr Romney’s campaign is in trouble. It is possible for a politician to insult some of the people some of the time and get away with it. To insult half the people indefinitely looks like a poor bet.
Second, he can "stand firm" here. That would be relatively new political ground for him, but at least he would be honest. Of course, it would alienate a significant percentage of the voting population.
Either way, Mother Jones and James Carter just threw Mr. Romney an anchor.