I feel like Matt's post doesn't quite convey what a big deal this National Intelligence Estimate is. So let me be more clear: It's HUGE. As of tomorrow morning, there is no politician in America, no media figure, no staffer, who can credibly say that they didn't "know" that Iran's nuclear program was much less significant than had been reported. "We judge with high confidence that Iran will not be technically capable of producing and reprocessing enough plutonium for a weapon before about 2015," the Estimate says. "We assess with moderate confidence Tehran had not restarted its nuclear weapons program as of mid-2007, but we do not know whether it currently intends to develop nuclear weapons."
So they halted their program in 2003, most likely have not restarted it, and in any case, are almost a decade away from creating a nuclear weapon. I also want to highlight this part: "We assess with moderate confidence that Iran probably would use covert facilities— rather than its declared nuclear sites—for the production of highly enriched uranium for a weapon." A quick bombing run would not disrupt their hypothetical program -- you would need to either flatten the country, or invade and overthrow the regime. So when you hear politicians talking about the Iranian program, understand that that's what they're talking about doing.