Columbus Business First has a good article on Marcellus production:  "The Marcellus is far and away the biggest natural gas producer among the top six shale plays, dwarfing production totals from the much ballyhooed Eagle Ford and Bakken plays in Texas and North Dakota, respectively. To put things in perspective, Associated Press reported that if the Marcellus region were a country, its natural gas production would rank third in the world after Russia and the rest of the United States."