I've made a list of prime places to travel to view autumn leaves in and around Jeollanam-do. The tourism authorities consider the peak times in the region to vary from October 29th through November 11th, 2010.
Plenty of excellent places for hiking among the colorful foliage, including Jirisan, Mudeungsan, and Baekyangsan.
http://briandeutsch.blogspot.com/2010/10/viewing-fall-foliage-in-and-around.html