Why yes, there has been a new Fallout game announced.  Kotaku is reporting that the game will be released next year and available for PC, PS3 and Xbox 360.

Pete Hines from Bethesda revealed that Fallout: New Vegas will not be a sequel to Fallout 3, however it will take place in the same universe.

Expect the same RPG format and not to worry, this game will not be an expansion pack or party game.

Thank you to both Kotaku and Joystiq.