Rachel Maddow had this great segment last night looking back at the 1979 Ixtoc I oil spill in the Gulf (in only 200 rather than 5,000 feet of water), showing that the technology for stopping offshore spills of this type basically hasn’t changed in 30 years. They used a top hat; it didn’t work. They used dispersants; they didn’t do the full job. They used a junk shot; no dice. They used a top kill; nope. Two relief wells finally allowed a capping of the well, nine months later. As Rachel noted, the only technological advancement in the offshore oil industry seems to be drilling deeper, not dealing with the consequences of an accident.

Consider the source, but both BP and Admiral Thad Allen (who’s overseeing the effort for the Coast Guard claim that this time, the top kill is working.

Engineers have stopped the flow of oil and gas into the Gulf of Mexico from a gushing BP well, the federal government’s top oil spill commander, U.S. Coast Guard Adm. Thad Allen, said Thursday morning.

The “top kill” effort, launched Wednesday afternoon by industry and government engineers, has pumped enough drilling fluid to block all oil and gas from the well, Allen said. The pressure from the well is very low, but persists, he said.

Neither government nor BP officials have declared the effort a success yet. Officials caution that only after the cementing is complete and the well is sealed can the top kill be called successful.

BP has made enough claims during this process that they need to be careful making any others. Even Fox News anchors recognize they cannot be trusted. Enough mud has apparently been pumped into the well to stop oil from being pumped out, but that could change; it’s basically a pressure battle. And importantly, capping the well this very second would still mean untold millions of gallons of oil on and below the surface of the Gulf. But capping the underwater gusher is clearly a top priority, and right now they’re claiming some success on the top kill.

Meanwhile, President Obama will hold a 12:45pm ET news conference to update new rules on offshore drilling. He will reportedly extend the “moratorium” on new deepwater permits for another six months (how many permits will actually be granted during this moratorium? Will he put it in writing?) and cancel projects off the Virginia coast, in the Western Gulf and Alaska, as well as issue new oversight and safety standards. I expect the media questioning to be tense and at times combative.

UPDATE: Among the other announcements today will be that the director of the Minerals Management Service has been fired.