Im in northwest Arkansas. I do see some rigid stuff on the trails but not much, more hardtails and lots of full susp. One guy had a redline single speed, he ended up keeping it single but put a shock on it. Its a tourist type town, and most people who are riding have driven several hours at least to get there, so I see more dedicated riders and racers. They tend to have newer bikes.
So mostly its all high end new stuff, or someone local trying a murray. I'm sure that I am not the only guy on a twenty year old bike, but it seems it always gets comments when I am out, and a lot today, which is what kind got me thinking about it. A lot of people have never seen a level top tube and come over to look. I worked at the park where the trails are a few years ago, and kept my old Puch mountainbike with moosebars, thumb shifters and lugs parked outside the office. People who stayed in the cabins for the weekend to bike were suprised when they saw me riding it to check things out in the park. They mostly thought it was a display! Oh, and for the record, no one has ever realy been a dick. Maby a little smug, but not that bad.