It seems a Service Mark application was filed with The United States Patent & Trademark Office the other week by Bethesda Softworks for "Fallout," its long running and highly acclaimed video game series.
This particular filing, however, included the following explanation: "Entertainment services in the nature of an on-going television program set in a post-nuclear apocalyptic world."
The filing took place on January 8th. The day after, American voice actor Erik Todd Dellums tweeted "There may be more of the Dog coming!" - referring to his Three Dog character in "Fallout 3". In that case though he was likely hinting that the character would return for another game.
A live-action series is the least likely considering the budget, but an animated or CG-animated show? Quite possible.
Back in October, Fox and EA announced plans for an hour-long TV show based on the "Battlefield: Bad Company" games. In the few months since though, no further information has been revealed.