And it appears that Christopher Guest is not going to be finished with the folk once "A Might Wind" is released. Look what else I found that he has in development:

Baba Said There'd Be Days Like This, starring Parker Posey

Oksana Sotnikow (Parker Posey) is a celebrated soloist in the Red Deer, Alberta-based Ukrainian dance company Rzeczownik. But she dreams of the day her talent and drive will catapult her out of her one-horse town and into the position of principal dancer in one of the flourishing folk dance theatres of Brighton Beach, New York. With the assistance and coaching of her choreographer and fiancé Don Kostyk (Eugene Levy), Oksana dances her way through a series of Canadian dance competitions, where she continually butts heads (and feet!) with her nemesis, Brenda Majiwska (Catherine O'Hara). But Brighton Beach is only big enough for one prairie-bred hoofer with a heart of gold. Will Oksana be awarded the audition before the legendarily demanding Godfather of eastern European folk dance, Myron Horudko (Christopher Guest)? As Oksana triumphs over adversity -- blistered feet, aching knees, and a pair of boots that "mysteriously" go missing only to turn up later in the trunk of Brenda's car -- she ruefully recalls, "Baba said there'd be days like this."