Given the title (insinuating time travel, I'd imagine) and the little UFO on the board during Dr. Jones' lesson, it's definitely looking more and more likely that Die Glocke will be central to the plot, if not the actual core MacGuffin itself.
Man, I am so in. Mangold fits this world and character like a glove while also seemingly evolving everything past what we last saw in 2008/1957, and it feels like Ford hasn't missed a beat.
Also, check the trailer description on YouTube to see George Lucas officially credited as exec producer alongside Spielberg.