Well, given that Democrats now have majority control in Congress, if we elect a Democratic president some stuff might actually get accomplished.

Though Obama would still be the best choice (IMO) if he were white, you can't argue that being black carries some weight and might encourage the rest of the world to take another look at America. I think it would relieve some of the sentiment that 70% of Americans and pretty much every other country has that America is retarded (in its current political state).