The tongue-in-cheek answer to what are they draining is why care?
The big question is how closely spaced are they planning to drill laterals. They have indicated as tight as 500 feet. The length of the lateral would determine the number of acres per well. If you currently have wells at 1000 feet apart, you will likely get more wells. (Eventually)
As a landowner, the hope is that they will get the highest amount of gas in place as possible.
Perhaps with the Reduced Cluster Spacing methods which they are currently using, they get a far more extensive network of fractures close to the well bore. More rock exposed, more gas freed, and more surface area within the network for gas to desorb once the pressure goes down, thus giving them a higher ultimate recovery.
Just my opinion.
When they talk about wells that are 5 , 10 , 20 bcf how many acres of land are they draining. 80,100,120 ?