According to IESB, the Buffy the Vampire Slayer creator is at the top of the list of candidates to helm the superhero picture.
The site insists that the report is "not an April Fools' joke".
Whedon's representatives have not confirmed the claim.
The Dollhouse producer has a history with Marvel as a comic book writer for Astonishing X-Men and The Runaways.
He is currently in production on horror film Cabin in the Woods, which he wrote and is producing. Whedon directed the 2005 Firefly spinoff film Serenity.
Zak Penn (The Incredible Hulk, X-Men: The Last Stand) wrote the Avengers screenplay.
The film is currently scheduled for a 2012 release.