That is a very ify question. I do not believe at the present time that the drilling activity would make it a issue unless of course the O&G really desired the lease. With as much land as thee is to drill on they can simply dill else where and hope to come back to a area . Supply and demand will answer that question in the future. My bet is that if you are not leased, Oil and Wet Gas prices remain fairly high with a good stable market, that hold outs will be of way higher value.
This is an example from Pennsylvania - a good friend of ours has only 2.5 acres in Washington County, in Hickory township, which was one of the first areas to be drilled. It is very convenient to the MarkWest processing plant, a real hot bed of activity. He held out. They simply said "buh bye". All of his neighbors are getting royalties and he gets nothing. He regrets his decision. I'd say it depends a lot on how many acres you have, since it is so easy for them to divert around small parcels. Big parcels - not so easy.