West Texas is so flat and featureless, you can kind of see why the state legislature voted to raise the speed limit to 85mph (It's already 80 mph--did you know that?). That's the funny thing about geography... the speed of travel is inversely proportional to the number of people living in the area. New York is dense, so travel there is snail-like. Outer space has very few humanoids, so we travel there at roughly 15,000 mph. Since West Texas also has few humanoids, locals think it's just fine to go really fast there, too. And yes, it makes sense to go 85—if the driver is above texting age, and below corrective-vision age. So there's like a 2 year window.
And when the speed limit is 85, will they pull you over at 90? Probably not, it's Texas... where fast driving is a birthright. Not sure if that tradition dates back to Sam Houston, though. He was lucky to make 85 miles a week. (Update 9/1/2011: Today, 85 mph becomes the state's maximim legal speed, although there are not yet any stretches of highway approved for the new limit. Speeders, be patient.)