McCain can still use the experience angle as Palin is the only one of the 4 that ahs any executive experience.

I do think this is a political move, as is every other VP. Palin will steal away some of Obama's Hillary supporters. She will hurt him even more with the blue collar. She will further hurt his washington insider attacks.

At the very least, Palin will neutralize Biden and IMO give a bit of a push to McCain in areas that Obama was already struggling.