Mr. New Vegas is an AI programmed by Mr. House before the Great War to be the DJ of Radio New Vegas, a job he still performs over two hundred years later in 2281. He is heard in-game on the radio, but never actually seen.
He makes comments and gives advice on the Courier's active quests, such as revealing what the Courier must do or is going to do. Much like Fallout 3's Three Dog, Mr. New Vegas also reveals some future details of the ending of Fallout: New Vegas, including the possible takeover of the NCR, Caesar's Legion and Mr. House. In addition, Mr. New Vegas comments on the outcomes of major quests the Courier has completed.
Mr. New Vegas rarely mentions the Courier specifically, possibly because of lack of information (except when the Courier leaves Doc Mitchell's house). This is in contrast to Three Dog who knows the Lone Wanderer, describing him/her as "the kid from Vault 101".
Mr. New Vegas is voiced by real-life Vegas-based star Wayne Newton, also known as "Mr. Las Vegas".
Mr. New Vegas' line, "Mojave, mo' problems. Am I right folks?" is a reference to the rapper Notorious B.I.G.'s song "Mo' Money, Mo' problems." This line is only heard if the player takes the Wild Wastelandtrait.
Occasionally, Mr. New Vegas will say, "You're nobody 'til somebody loves you, and that somebody is me. I love you." This is a reference to the song "You're Nobody 'Til Somebody Loves You" by Dean Martin.
Mr. New Vegas will occasionally say "Tensions are brewing in Freeside between the ruling gang known as the Kings and the large number of NCR squatters seeking refuge there. The leader of the Kings, who would only identify himself as The King, voiced his displeasure, calling NCR citizens, quote, the devil in disguise. He added he didn't want to see any NCR in the ghetto, and called for a mass, quote, return to sender." This is a reference to the Elvis Presley songs "Devil in Disguise", "In the Ghetto", and "Return to Sender".