Band Little Big Town; Garth Brooks' daughter Allie Colleen; judges Katy Perry, Luke Bryan, Paula Abdul, and Lionel Richie ("American Idol"); Rachael Leigh Cook, Rosario Dawson, and Tara Reid on the 20th anniversary of "Josie and the Pussycats"; guest co-hostess Clare Crawley ("The Bachelorette"); the cast of "F9", the next "Fast and Furious" movie; Aaron Rodgers and Shailene Woodley;—anonymous