Marvel's Age of Ultron event is still pretty fresh, so it's interesting to see it announced as the basis for the next Avengers flick, which is officially titled Avengers: Age of Ultron.
Brian Michael Bendis's tale primarily took place throughout a 10-issue series, in which we're whisked away to a future that sees superheroes hiding from an all-powerful Ultron and his Sentinel forces. They eventually kick off a time-jumping scheme to take down Ultron in the future to prevent him from attacking the present. Wolverine has a different plan, however, as he leaps to the past to stop Henry Pym from creating Ultron in the first place, even if it means killing him.
Joss Whedon appeared to make the reveal right after the Guardians of the Galaxy portion of Marvel's panel, showing a brief teaser that built up to Ultron's helmet. It's unclear just how closely the Age of Ultron film will follow the comic, if at all, especially with some of its characters split across different studios.
Avengers: Age of Ultron is gunning for a summer 2015 opening.