The evidence strongly suggests otherwise.
Does Fallout 4 exist? The post-apocalyptic, action-RPG hybrid from Bethesda Softworks probably does. Will it be announced at the upcoming E3 convention? Probably. Will it be coming to the Xbox One as an exclusive title? This is where things get confounding.
According to NeoGAF, there have been several instances of Fallout 4 being mentioned. The Cheapy D podcast talked about third party exclusives for the Xbox One and cited Fallout 4 as a possible example. Meanwhile, Giant Bomb founder Jeff Gerstmann stated on Tumblr about major exclusives being obtained by both Sony and Microsoft, with a theoretical situation mentioning Fallout 4 as being exclusive to the Xbox One.
Another Giant Bomb member Patrick Klepek restated on the Bombcast about Fallout 4 being exclusive to the Xbox One, and then there’s evidence of the timed DLC that Bethesda has done for the Xbox 360.
But for the life of us, we know that no single AAA blockbuster will ever risk releasing on a single console anymore unless it is a first party title or buckets of cash are being spent to ensure some sizable return on investment (and even in those circumstances, it’s a timed exclusive).
Then again, in this day and age, you can never say never. We’ll find out at E3 2013 just what Microsoft and Sony have in store for us, and whether Fallout 4 – if it indeed announced – will be exclusive or multiplatform after all.