When asked if it was a teaser to a new Fallout, Bethesda's Pete Hines tweeted back with: "Are you talking about the Vine thing? Guess again :-)"
So we should just take his word for it, right? WRONG!
Before Elder Scrolls 5: Skyrim released, Bethesda confirmed that there were no werewolves in Skyrim. The game released, and guess what... F*CKING WEREWOLVES! Far be it from me to call you a liar Pete Hines, but you're a liar. Maybe... who the heck knows. This is just another game company creating a very ambiguous teaser to a teaser for an announcement.
Some popular beliefs as to what this may be teasing are: Wolfenstein, Fallout 4, a Fallout MMO, and possibly Bethesda's video guy being on acid.
What do you think?