At Comic Con’s Marvel panel, Joss Whedon announced the official title for the second Avengers film, The Avengers: Age of Ultron. Have a look at the new logo here:
In the comics, Ultron is a robot created by Hank Pym, aka Ant-Man. So does this mean that the first appearance of Ant-Man will be in the Avengers: Age of Ultron? Edgar Wright’s Ant-Man film is due shortly after the release of Age of Ultron, so it’s entirely possible that the character will first be introduced in Age of Ultron to build up some familiarity for the character before his own solo film.
Avengers: Age of Ultron will open in theaters on May 1, 2015. I would imagine that cameras would start rolling soon to make that date. Not to mention they are going to need some time to attempt to outdo the first film.