Obama is currently the hot ticket because many Dems are desperately seeking anyone but Hillary. The Reps are in a similar fix because they have no one who appeals to the majority of their voters, which is why Thompson is so appealing despite not having announced. So 2008 is still up in the air.
Also, if you look at the actual reaction of folks to the university massacre, you'll see little reaction in the mainstream media. That is because most people see the obvious, which the biased mainstream media doesn't want to talk about: Criminals and whack-jobs don't give a fig about gun laws, only law-abiding people do, and law-abiding people don't go on rampages. Technically, the massacre should not have happened; the school had a gun law against carrying guns on campus. Well, now we know how much protection such laws actually provide. And most Americans know that, so that's why there's been a surge in gun sales. Most Americans know that you must rely on yourself to stop some criminal or whack-job from killing you and your family. They don't want to be unarmed when the next Cho comes around. I think this massacre will actually turn people off about gun laws.
Ironically, however, most people don't link the 2nd Amendment to their right to protect themselves.
Regardless, the future is always in flux. There's very little downside to stocking up, other than storage space, and usually lots of upside, such as beating cost increases and having plenty of ammo on hand when you want or need it. 2,000 to 4,000 rounds is probably a good minimum, if you want to stay proficient and still have something for SHTF situations.