Is this the marcellus shale?
And are you referring to a non-surface lease ( drillers are not allowed on the surface of your property?)
In our area (Southern Tier NY) this has been a very hot topic-- many landowners for and against. Study up on how Pennsylvania has fared with gas drilling. My biggest concern is the amount of water needed for the fracking process, and also the disposal of this water/sand/chemical waste.
I would not want to see it get into our watershed. Others are concerned about the impact of heavy trucks on their roadways. Educate your self on the fracking process, if this is what the will be using.
If they can not drill unless you sign, take the time to do some research. Your county may have a landowners group which negotiates pricing- to make sure you're not being taken advantage of. Sometimes attorneys work with groups to make sure landowners know what they're agreeing to.
Here's one blog you might want to look at:
http://shaleblog.com/category/marcellus-shale/
There's an entry in June about Ohio.
Also from Cornell University:
http://cce.cornell.edu/EnergyClimate...s/default.aspx