Thank you for providing a none of the above choice.
The way I see it, they are both practically the same. They both follow a widely interventionist, police-the-world type foreign policy. Although Obama ran as the "peace" candidate and vowed to bring the troops home, we have seen nothing of the sort, only more warfare and more death and more spending on "defense" (there's nothing defensive about it).
They both believe that the government has the power to lift us out of recessions. Neither believe that the government is what causes the business cycle in the first place, and both see increases in the government's reach in the economy as a good thing.
Both trample on our rights to life, liberty, and property, most notably through taxation, the Patriot Act, suspending habeas corpus, wars, inflation, and not reducing the size of the government one bit. In fact, both of them increased the size of government to monumental proportions. It's scary, really, to think about how much the government does, how much it has control over, and what all it could do with such power.
In sum, one has an "R" next to his name, and the other has a "D". That's about the extent of their differences. There has been no real change, no real solutions, no decreasing government, no improving the status of liberty among the citizens, no respect for what the Constitution recognizes, and certainly no push toward libertarianism.