The news was reported by EW.com.
Whedon is best known as the creator of the cult-favorite TV shows "Buffy the Vampire Slayer," "Angel," "Firefly" and "Dollhouse." His only film directing credit is for the big-screen "Firefly" follow-up "Serenity."
Set for a May 4, 2012, release, "The Avengers" movie is expected to feature the comic-book icons Iron Man, Thor, Captain America and the Incredible Hulk.
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