It's called Wrangler (by Alexander Henry Fabrics) and I thought it was mostly gone/out of print except for a bit showing up in some eBay auctions.
I got four yards of it a while ago, and while at jadecat9's Christmas eve crafting/dinner party started cutting out a camp shirt from it. Of course, since I was being compulsive about matching up up the patterns so all the cowboys would stay pretty, that uses up lots and lots of fabric. I'd hoped to make a western yoked shirt as well but that obviously wasn't going to happen.
Someone told me that Eddie's Quilting Bee in Mt. View actually had some in stock, but today I was in Hancock Fabrics to get some interfacing and found a bolt on the 30% off rack! So now I have 6 1/2 yards more to play with, plus some nice contrasting blue.