Singer Mariah Carey; author Jonathan Safran Foer ("Eating Animals"); latest castoffs from "So You Think You Can Dance."

Actress Mo'Nique ("Precious: Based on the Novel "Push" by Sapphire"); "The Biggest Loser" castoff Abby Rike; Justin Bieber performs.

Actor Jim Carrey ("A Christmas Carol"); singer Faith Hill discusses her new fragrance.

Halloween Show: singer Kellie Pickler; singer Rick Springfield; Science Guy Steve Spangler.

Singer Taylor Swift; Tim McGraw performs; backup dancers from "Michael Jackson's This Is It" perform.

Journalist Katie Couric; TV personality Kate Gosselin; actress Gabourey "Gabby" Sidibe ("Precious: Based on the Novel "Push" by Sapphire").

Talk-show host Jimmy Kimmel; author Deepak Chopra ("Reinventing the Body, Resurrecting the Soul").

Actress Hilary Swank ("Amelia"); Jay Sean performs; children's Halloween costumes.

Actress Alyson Hannigan ("How I Met Your Mother"); actress Julie Bowen ("Modern Family"); "Dancing With the Stars" contestants Mya and Dmitry Chaplin.

Actor David Spade; actor John C. Reilly ("Cirque Du Freak: The Vampire's Assistant"); Mika performs; a 10-year-old girl raises money for a no-kill animal shelter.