There was an asteroid that could have hit us last night, according to Fox News it hit, but they're just idiots. However why the fuck doesn't world governments take more interest in such things. It pisses me the fuck off. They are more concern over WHEN the Apocalypse is going to happen than how to prevent it because they believe they'd go to god damn heaven.
According to that Recovery website, a third of the money apart of Obama's plan is going to Sciene and Research. I hope this includes the asteroid coming in 2012.
If you wait until the asteroid is that close to the Earth before trying to deflect or destroy it, you're already taking too much risk. The delta-v of an early deflection attempt is orders of magnitude less than what's required when the mass is making the final approach to the Earth. But in order to achieve that early attempt, you have to have a space-faring capability in the first place ... like manufacturing and launch capacity from lunar bases. That means extensive living quarters on the moon, which means transit of personnel from the Earth, and asteroid mining for volatiles that are too expensive to ship to the lunar surface.
In a sane society, we either make no investment in space at all and just squat here and take our chances, or we invest in a real space-faring capability ... which means a waystation in Earth orbit, common transport lines to the moon, living and manufacturing areas on the moon, and asteroid mining missions. Naturally, with enough of that going on, some entrepreneurs will strike out for Mars and try to cover their costs with selling exploration information they get, and then start in on Terraforming the planet. Emplacing a launch loop on the Martian surface should be fairly easy, considering the low temperatures and very low atmospheric pressure ... so for the first century or two, surface transport should be very cheap. Later on, as the Martian atmosphere thickens from Terraforming, the costs will rise slightly, but enough people will live on Mars at that point to make it worthwhile.