Royalty payments to mineral owners probably have exceeded the $5 billion mark, according to estimates done by the good folks at www.marcellusgas.org/graphs/PA#royal_current. Nearly 50% of the total payments have flowed into Washington and Greene counties. Both are located in Southwest Pennsylvania, where Marcellus gas wells not only have been drilled in large numbers but also have been connected to pipelines and are delivering gas to consumers.
The Marcellusgas.org folks also have interesting data on how much counties will collect in impact fees. They project that Bradford, Tioga, Washington, Lycoming, Susquehanna, and Greene are projected as the top 6 counties for impact fees.
The impact fees are based on wells drilled or developed, while royalty payments are based on gas volumes flowing into pipelines. Currently a lot of wells drilled are not connected to pipelines in Pennsylvania.