It's widely accepted that Bethesda is working on a Fallout something or another. It's likely the company is working on "Fallout 4," and it appears the game will be set in Boston.
Alleged casting documents sent to Kotaku suggest the next Fallout game will take place in Boston. However, the site points out that "Fallout" is never mentioned in these documents. Instead, they are for a project codenamed "Institute."
"War. War never changes," the script for the casting call begins. This is the class introduction used in every previous mainline Fallout game. However, as evidenced by the casting call, it appears Ron Perlman will not be reprising his narrating role for this new title.
Other documents received by Kotaku detail a mission set in the Institute--Fallout's take on MIT. There are other Fallout locations that have been mentioned in previous games, like the Commonwealth.
When contacted regarding this rumor, Bethesda told us this: "Thanks for reaching out. In regards to the Kotaku article, we don’t comment on rumor and speculation."