On May 8, 2012, Marvel Studios announced The Avengers 2. The movie is currently in development and is scheduled for release on May 1, 2015. Joss Whedon is on board to write and direct the sequel.
Not much news yet but lots of rumors. The cast is rumored to consist of Chris Hemsworth as Thor, Scarlett Johansson as Natasha Romanoff/Black Widow, Robert Downey Jr. as Tony Stark/Iron Man, Jeremy Renner as Clint Barton/Hawkeye, Chris Evans as Steve Rogers/Captain America, Cobie Smulders as Maria Hill, Samuel L. Jackson as Nick Fury, Mark Ruffalo as Bruce Banner/The Hulk, and Anthony Mackie as Sam Wilson/The Falcon.