We've come a long way, baby...

The Macondo well may be sealed and "dead," but the impact of the Deepwater Horizon disaster is going to be felt for some time to come. We're spending the whole hour wrestling with some of the unanswered questions and lingering issues that the BP oil spill has left in its wake. To help us navigate these dirty waters, Robert Hernan, author of "This Borrowed Earth: Lessons from the Fifteen Worst Environmental Disasters Around the World" joins us for the hour.

Also, check out our timeline of the entire disaster, spanning from the Deepwater Horizon's construction in 1998 through when it was declared "dead" on Sunday.

Everyone heard the rumblings in the distance, but with the second-quarter earnings reports this morning, BP finally dropped the bomb: Tony Hayward is out. He'll step down from his post as BP's CEO this October. It's been reported that he’ll be sent to Russia to work on a BP joint venture there.

BP has successfully installed and closed a 75-ton cap atop the gushing oil well in the Gulf of Mexico and for the first time in 85 days, oil has stopped flowing into the ocean. While this may come as a huge relief to many whose lives and livelihoods depend on the Gulf waters, some experts estimate that up to 184 million gallons of oil may have already contaminated the sea. (For a sense of scale, imagine one of the world's largest super-massive cruise ships filled up to the brim with sticky crude oil.  Now imagine another one, the exact same size, also filled to the brim with oil. That's roughly 150 million gallons.)