It appears to me that in spite of their bluster, the Dems were scared to death of a shut down. Fox News posted a poll that indicated the combination of Obie+Democrats would get just as much blame, if not more, for it.
IMO, the Republicans damaged their negotiating position when they took shut down off the table. That is the difference between Gov Palin's approach to negotiation and the current Pubs.
I think the GOp blinked because they wanted to blink. they don't really believe in what they are saying but they know they have to show some cuts to keep their positions....nothing else really explains it.