Bethesda Softworks posted a brief teaser video on its Twitter account this morning, hinting at a future reveal with music imagery.
The four-second Vine clip (embedded below) begins with shots of barbed wire, then shifts to glimpses of old, old music. The first appears to be a 33 1/3 LP by The Moonbeam Trio, directed by George Shackley, called "Planned program service program no. 416." No year is listed for the LP, but the Library of Congress has recordings of the individual pieces dating back to the 1910s, including "Chanson de Florian," "Grandfather's clock" (starting at 1:07) and "I cannot sing the old songs." The video ends with images of looks to be sheet music for "Air on the G-string" by Johann Sebastian Bach.
It may be teasing something related to the Fallout universe. Music by Bach appeared in Fallout 3 on Agatha's station. Fallout: New Vegas senior producer Jason Bergman also retweeted Bethesda, saying, "CONSIDER YOURSELF TEASED."
Update: Pete Hines, Bethesda's vice president of public relations and marketing, dashed hopes on Twitter of a Fallout-related reveal, saying, "Guess again."
Update 2: Bethesda posted another teaser on April 17. Sunflowers feature heavily in the second video — first, they're just there, and then they're on fire.
Update 3: Bethesda posted the third and apparently final teaser on April 18. This video features a tall window. The reveal will come tomorrow, April 19, on IGN.