There's a link on EnergyBulletin about NG in the Barnett Shale of North Texas.  

The U.S. Geological Survey estimates there are 26 trillion cubic feet of natural gas equivalent in the Barnett Shale, although no one really knows how far the play extends.

Sounds plentiful, but the NG is trapped in small crevices that must be fractured, so I would think there would be considerable setup costs.

http://houston.bizjournals.com/houston/stories/2005/11/14/story1.html

Yes, I was told that this area was the prototype for drilling. A successful well had been drilled there. That a similar operation (Maverick Oil & Gas?) was going to use the same type drilling for Eastern AR.
My parents live just south of Fort Worth and report a frenzy of NG drilling all around the area. The FW Star Telegram has had a number of stories on this I understand.

The point is: is this drilling in the Bartlett Shale a sign of how desperate things really are? I mean it seems like this is pretty difficult to get to. How realistic are these estimates of the amount of gas available? How much supply is this in years?

There are alot of artifacts in my County.

With one of the County Historians (aka Geezer) by my side, I can locate old rail beds, brickmaking facilities, old tile drains, and... an old gas well, abandoned.

Why was the well abandoned?

I think, like you, dex3703, because the gas is in pockets, fractured.  And it wasn't economical.

These guys plan to put in a well every 40 acres !? if they hit with the well they're now drilling.

Is this possible?  How many rigs are we talking, and is a water injection system necessary for each well?  I was told a rice irrigation well (12 " diameter pipe) was needed to drill.  That's alot of water.

James