It's worth pointing out that for the decade ending in 2008 (ie, before the Deepwater Horizon spill), natural oil seeps accounted for 9 times more oil discharged into U.S. waters than all the spills in the oil industry put together.
Still, the saga of the Ocean Saratoga and its nearby well highlights a worrying trend: from 2000 until 2009, oil spills on offshore rigs nearly quadrupled, and the number of barrels spilled per year increased compared to overall production, according to this analysis of records from the Minerals Management Service.
More broadly, there is the massive uncertainty about how many spills go unrecorded. The MMS has shown itself to be an inept regulatory agency riddled with corruption, but assumptions are dangerous.
What we do know is that 1. the Gulf ecosystem can handle a constant, relatively small amount of oil that naturally seeps into the sea every year, and 2. when independent observers start looking hard at oil and gas extraction activities in the Gulf, previously unreported leaks are found.