The current numbers for the amount of oil leaking in the gulf before June 3rd have just been updated to up to 40,000 barrels a day. That’s a large number but I really think it’s hard to put in to perspective.
A good way to put that in context is to compare it to the amount of oil the USA uses a day. The US Energy Information Administration says the USA in 2009 used 18,686,000 barrels of oil a day (chart).
(18,686,000 / 24) / 60 = 12,976 barrels a minute
40,000 leaking barrels a day / 12,976 = 3.08 or 3 minutes and 4.8 seconds
So while that’s a lot of oil, it’s only a small fraction of the oil we use a day. Even over the whole 47 days between April 20th and June 6th only 2 hours and 25 minutes of oil were spilled.
I’m not saying that it’s not a catastrophic disaster but every day we pollute by several magnitudes more and it’s good to keep these things in perspective.