Palin is two days of headlines and two months of headaches for the GOP.
The reason why the punditry is going bananas over the pick is that it defies all logic and everyone is seeking some rational reasoning as to why McCain picked her-the Occam's Razor explanation for the selection (complete, gross miscalculation and incompetence) is just too devastating to the McCain campaign.
Also, every liberal and a good chunk of the reasonable moderates in the country are quietly-though they aren't going to admit it-looking at her views of science, aborition, contraception, global warming, the environment, and energy and thinking to themselves "shit, if that old fuck dies we are going to be stuck with THAT monster". Did no one think of the consequences of putting a hard-line movement conservative on the ticket?
I swear, part of me thinks that the GOP is using 2000 or 2004 era voter registration numbers to determine policy. If they wanted to win, they'd take their own smaller base for granted and run to the center, and hope that fear of the abortion holocaust and The Godless Communism would scare them up enough to get out and vote.