Bethesda's Fallout will be based on a new version of the Fallout 4 engine, so there won't be any big surprises, other than better rendering and lightning more optimized for current consoles and PC hardware.
As noted, the game will be an "online-only" experience that will allow players to team u pin multiplayer for some fun in West Virginia, where the game is set. It will also offer a single-player mode, called "solo mode", but this does not mean that it will be an offline game.
Bethesda also said that Fallout 76 will be four times larger than Fallout 4 and still offer building options with new items added to the Construction and Assembly Mobile Platform (C.A.M.P). Since it will be an online only game, this pretty much means it won't support modding, which was a big thing for PC users.
According to the fresh trailer and information provided by Bethesda, Fallout 76 is set on Reclamation Day, 2102, twenty five years after the bombs fell, you will emerge from Vault 76.
Fallout 4 will launch on PC, Xbox One, and Playstation 4 on November 14, 2018, and there will be a B.E.T.A. (BREAK-IT EARLY TEST APPLICATION) phase sometimes later this year. Bethesda also announced the extremely limited Fallout 76 Power Armor Edition, which includes full-scale, wearable T-51 Power Armor helmet and a couple of other goodies.