At around 2:25 p.m. on Thursday, oil stopped gushing into the Gulf of Mexico for the first time in nearly three months. BP had carefully placed a cap over the geyser, gradually tightened the valves, and, as of Friday morning, it continues to hold. "It's a great sight," said BP's Chief Operating Officer Doug Suttles. At the same time, he urged patience saying "It's far from the finish line. ... It's not the time to celebrate." Here's the incoming analysis from reporters filing along the gulf coast:

  • Where Things Stand Now Susan Daker and Russell Gold at Wall Street Journal report: "BP said Thursday it shut the valves on a new cap on the well as it tested its latest effort to contain the massive spill... The test could take up to 48 hours to complete. If the results are ideal, the cap could be used to stop the flow from the well while work resumes on efforts to plug it permanently. More likely, a successful test will enable BP to siphon all the oil from the well to ships on the surface in a controlled manner, eliminating leaks until the permanent fix is made."
  • Where Things Could Go Wrong  The Associated Press reports: "If the cap holds, if the sea floor doesn't crack and if the relief wells being prepared are completed successfully, this could be the beginning of the end for the spill. But that's a lot of ifs, and no one was declaring any sort of victory beyond the moment... The worst-case scenario would be if the oil forced down into the bedrock ruptured the seafloor irreparably. Leaks deep in the well bore might also be found, which would mean that oil would continue to flow into the Gulf. And there's always the possibility of another explosion, either from too much pressure or from a previously unknown unstable piece of piping."
  • What Does Testing the New Cap Entail?  Mark Guarino at the Christian Science Monitor explains:
Testing of the new cap will take place over 48 hours. In that time, a team of scientists and engineers will use pressure readings and sonar to examine the condition of the well bore, which extends 13,000 feet down from the wellhead – which itself is 5,000 feet below the surface of the Gulf – to the reservoir of oil.

Engineers worry that if the well bore is damaged, oil could blow out the side of the well bore and form a new gusher elsewhere on the sea floor.

If pressure readings remain high, that will indicate that the well bore has retained its integrity – that oil is staying inside the well bore and pushing up against the cap. Low pressure readings would suggest that oil is escaping through cracks in the well bore, forcing BP to open the cap again and revert to collecting oil in surface ships.

At the White House, President Obama called the development a “positive sign,” though he cautioned that the operation was still in the testing phase.

In statements, Louisiana officials, including Gov. Bobby Jindal, said they were “cautiously optimistic.”

Officials at all levels played down expectations. Thad W. Allen, the retired Coast Guard admiral who is coordinating the spill response, told reporters on Thursday that the cap was primarily meant to be used to shut the well during extreme weather.

  • People Are Euphoric, Skeptical, reports the Associated Press: "Though a temporary fix, the accomplishment was greeted with hope, high expectations — and, in many cases along the beleaguered coastline, disbelief. From one Gulf Coast resident came this: 'Hallelujah.' And from another: 'I got to see it to believe it.'