“BP officials have repeatedly said there is no way to measure the rate of flow from the broken pipe. – link“

Given the fact that NOAA underreported the numbers in the first place and BP has no incentive to report actual numbers, I am inclined to believe the numbers carried on the Examiner. This is really scary:

If this thing blew, it could be like the Yellowstone Caldera, except from below a mile of sea, with a 1/4-mile opening, with up to 150,000 psi of oil and natural gas behind it.

That would be an extinction event.

It is not likely to happen, but it is within the realm of possibilities.

How do you estimate this?

Although the real number will never be known, scientists and others will create more specific estimates over time. I am pretty certain that the chain of events that lead to this catastrophe will also be dissected. However, I am not so certain that the punishment and/or deterrents needed to prevent a future accident similar to this one will be implemented.