Also slated to appear on " Tonight " are Olympic gold medal skier Lindsey Vonn , country music artist Brad Paisley , former Alaska Gov. Sarah Palin , Olympic gold medal snowboarder Shaun White , TV personality Chelsea Handler , Olympic speed skater Apolo Anton Ohno , singer Avril Lavigne , actor Matthew McConaughey , director Jason Reitman , Oscar nominated actor Morgan Freeman and " Today " co-host Meredith Vieira , MTV News said .