Bethesda officially revealed Fallout 4 for the Xbox One, PlayStation 4 and PC yesterday. The timing of the game's development has allowed the team working on it to be "more ambitious than ever" — and what's more ambitious than releasing a game that was revealed halfway through the year during that same year?
GameStop, Greenman Gaming, Amazon and Bethesda's own store have listed the game for a 2015 release. Of course, the release dates listed are placeholder dates, but they do point to a Holiday release.
The Bethesda store has updated their store to say "TBA " instead of "TBA 2015" like it did before. This move seems to be a push to keep the release a complete surprise until the official announcement during Bethesda's press conference on Sunday June 13.