Both Fallout and Elder Scrolls are two of the biggest gaming franchise in the history and they are both owned by Bethesda. Heck, it also made things easier for the game developer as they can produce both series closely with each other.
On the downside of things, this will not mean well for the future game Fallout 4. After all, it basically suggests that Fallout 4 will be built on the same game engine that is used on Elder Scrolls Skyrim. This is not something great since Skyrim’s graphics will only look decent at best when running on the latest gaming hardwares around.
There is also no doubt that Fallout 4 will be released to the Xbox One and PS4, thus, it requires a next-gen game engine to optimize the latest gaming consoles. However, that is unlikely to happen since developing a new game engine requires tons of research, time and money.
With that being said, it is highly possible for Fallout 4 to get released with Skyrim’s game engine. If so, then fans of the Fallout series should not have high expectations for Fallout 4’s graphics as it is not going to be extraordinary.