Obama should choose
Jim Webb as VP. McCain should choose
Mark Sanford as VP.
I would like
Chuck Hagel as VP for Obama but I don't think the Democrats would go for it. I would be satisfied with Hagel as Secretary of Defense however. Obama needs a ex-Military, White, Christian male as VP. Maybe even someone slightly racist to get the bigot vote.
I don't think he can afford to bring Hillary onto the ticket. Not only does she represent past politics but I don't think the people will vote for a black guy and a woman.