Fallout: New Vegas Add-ons

Caravan Pack
The Caravan Pack is a Fallout: New Vegas add-on that gives the player access to of extra items at the start of the game. It was announced as a pre-order bonus exclusive to Steam, Wal-Mart, Mighty Ape, and Play.com. It includes lightweight leather armor, the sturdy caravan shotgun, 4 repair kits, and a pair of binoculars.

Classic Pack
The Classic Pack is a Fallout: New Vegas add-on that gives the player access to extra items at the start of the game. It was announced as a pre-order bonus exclusive to the GameStop, GAME and EB Games chains of stores. It includes an armored Vault 13 suit, a weathered 10mm pistol, a Vault 13 canteen, and 5 stimpaks.

Mercenary Pack
The Mercenary Pack is a Fallout: New Vegas add-on that gives the player access to extra items at the start of the game. It was announced as a pre-order bonus exclusive to the Best Buy and JB-Hi Fi (Australia) chains of stores. It includes lightweight metal armor, a mercenary's grenade rifle, 3 super stimpaks, and 3 doctor's bags.

Tribal Pack
The Tribal Pack is a Fallout: New Vegas add-on that gives the player access to extra items at the start of the game. It was announced as a pre-order bonus exclusive to Amazon.com and direct2drive.com. It includes tribal raiding armor, a broad machete, 5 bleak venom doses, and 10 throwing spears.

Dead Money
Dead Money was released on December 21, 2010 exclusively for Xbox 360. It'll raise the level cap to 35 and have new achievements and new perks.

Future add-ons
Dead Money was first hinted via in-game graffiti. The textures for these graffiti are in a folder in the game files called "nvdlcgraffiti", and all the textures share the filename "nvgraffitisierra". Interestingly, this folder contains a number of other textures, sharing the filename "nvgraffitihonesthearts". These read:
 * ''"Where's New Canaan, anyway?"
 * "The Burned Man Walks!"
 * "Joshua Graham Lives!"

On what is apparently a completely different plot thread, Christine mentions that she was once captured by Father Elijah in the Big Empty, but was rescued by "a courier who wore a flag of the old world on his back", presumably referring to Ulysses. It is also stated in one of Dog's endings that:
 * "The new voice did not think of the Courier again until the battle at the Divide reached his ears. The battle between the two couriers, beneath the torn skies and the Old World flag... each bearing a message for the other. And the mutant prayed the Courier that had saved him... had been saved in return."

Both of these instances act as triggers for the Things to Come! challenge, seemingly confirming that these plot threads will be part of a future DLC.

Jason Bergman has stated that one thing that will not be appearing in a DLC is the ability to extend the game past the ending, á la Broken Steel, despite popular speculation.

DLC Announcement History

 * On October 18, 2010 Bethesda confirmed that there will be post-release DLC for Fallout: New Vegas.
 * On November 17, 2010 Dead Money was announced by Major Nelson and Bethesda.
 * On December 21, 2010 Dead Money was released exclusively for Xbox 360.