"Government, stay out of it!"
"Why isn't the government doing anything?"
The truth is, they can't, at least not directly. A federal law was passed after the Exxon Valdez accident in 1989 which gave the owner of the equipment the sole responsibility of oil spill cleanup, penalties and everything. The government can't do anything except provide oversight, which they've done (via the Coast Guard) since the day that the drilling rig blew up in April.
Who was President when that law was passed? Shrub Sr.
While, yes, the blame for spills should be heaped on oil companies in spades, there should have been some sort of clause in there for more possible intervention from the government. Perhaps then, we could get these kind of things cleaned up quickly (as long as, based on historical evidence, one of the Bush clan isn't in office) instead of having to wait while the oil company at fault is putzing around.