Bethesda just started up a live stream... people are saying 'New Vegas 2', 'Remake of Fo3' and other wild speculation is going on.
Dutch news sites are saying Bethesda *will* announce a new 'Fallout', sorry, could only find a dutch source so far..
http://frontpage.fok.nl/nieuws/795899/1/1/50/bethesda-teaset-nieuwe-fallout.html
Live stream is here, I'm waiting for the announcement to start... let's hope it's not a dud!:
(edit: Fallout 76 is a thing.)