Kenny Chesney had barely said good-bye to the thousands of fans gathered for the sold-out show at the end of Country Thunder -- the four-day annual festival held in Twin Lakes, Wis. July 22-25 -- when next year's headliner was announced. Rascal Flatts will be gracing the stage as the final act for Country Thunder in 2011.

Rascal Flatts are already spending much of their time on the road on the Nothing Like This tour, along with opening acts Kellie Pickler and Chris Young. The trio, comprised of Gary LeVox, Jay Demarcus and Joe Don Rooney, may soon need bigger buses, since the wives of both Jay and Joe Don are pregnant. In addition to performing sold-out shows, the busy guys are also working on an HBO miniseries, 'To Appomattox.'

This past year's Country Thunder line-up included Miranda Lambert, Sugarland, Kevin Costner, Luke Bryan, Jason Aldean, Billy Currington and Craig Morgan. No word yet on other performers for next year's festival. Click here to keep track of Rascal Flatts' schedule.