It would appear that Ken Burns' country music documentary that aired on PBS has lead to increased sales for artists who were featured in the series.
The day after the finale aired, 14 out of the 20 top-selling country albums on iTunes were artists who had been mentioned in the documentary. Waylon Jennings, Patsy Cline, Willie Nelson, Emmylou Harris, Jimmie Rodgers, Nitty Gritty Dirt Band and Kris Kristofferson all saw a big jump in sales, usually the day after their episode aired.