Rumours are rife in indicating that Fallout 4 is being developed by Bethesda and it will be released somewhere next year. However, if fans are to follow the latest rumour, Fallout 4 is said to get cancelled from production.
Apparently, Bethesda has decided to drop Fallout 4 due to an argument with the series original creator, Interplay Entertainment. In detail, Bethesda idea to turn Fallout 4 into an MMORPG title got blocked by Interplay. It resulted in the frustrated Bethesda to drop Fallout 4 from production.
Then again, this is just a rumour and it is best taken with a pinch of salt. Seeing the huge profit potential with Fallout 4, it is unlikely for Bethesda to not develop the game at all.