Disney currently has an untitled Marvel Studios movie set for May 6, 2016, which is the same release date for the Batman Vs. Superman movie.
They also mention that a Guardians of the Galaxy cartoon is planned for next year as well, which would help with building of the audience.
It's said while a sequel does depend on how well Guardians of the Galaxy performs at the box office this August, it seems as if the movie will do well as everyone has been really receptive to James Gunn's vision.
The May release dates for Marvel have previously been used for their big guns such as Iron Man and The Avengers. Perhaps Guardians of the Galaxy 2 will see some form of the cosmic Avengers.
"Guardians of the Galaxy" has an August 1, 2014 release in the U.S.
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