From left to right: Robert Downey Jr., Clark Gregg, Scarlett Johansson, Chris Hemsworth, Chris Evans, Samuel L. Jackson, Jeremy Renner, Mark Ruffalo, writer/director Joss Whedon and Marvel head Kevin Feige. (Click to Enlarge)

Marvel Studios brought out the big guns for their panels at the San Diego Comic Con this weekend. In addition to showing off the first footage from Thor and The First Avenger: Captain America, they assembled the cast of the upcoming Avengers film. Joss Whedon (Serenity, Buffy the Vampire Slayer) was officially announced as the director of the film. Marvel also announced that Mark Ruffalo would indeed be replacing Edward Norton as Bruce Banner/The Incredible Hulk, as had been rumoured. For those unfamiliar with the comics, The Avengers are a team of Marvel Comics superheroes made up of Iron Man, Captain America, Thor, The Hulk, Hawkeye, Nick Fury, Black Widow, various “lesser heroes” and  S.H.I.E.L.D agents.

The film is basically the biggest comic book movie anyone has ever attempted to make. My own personal feelings about Joss Whedon aside, I tend to agree with people who say he is a great choice for such a large ensemble piece. Whedon has made a career out of ensemble pieces full of witty dialogue and clever retorts and Serenity proved he could do big budget action. It’s going to be a tough balancing act, but at this point you would be hard pressed to name an a suitable alternative.

The success of The Avengers is going to depend greatly on how well the Thor and Captain America films do critically and financially. With the Iron Man and Hulk films laying the groundwork for this new contiguous Marvel film universe, the studio is off to a pretty good start. It is the upcoming films on the Marvel slate that have some heavy lifting to do: Joe Johnston’s Second World War Captain America film and Kenneth Branagh’s cosmic Thor adaptation have their work cut out for them if The Avengers is to be a success. Fan reaction to footage from both films has been overwhelmingly positive, so things at least seem to be on the right track.

Marvel has launched a teaser site for the film, complete with the famous “A” logo, which you can see here.

The Avengers is set for a May 4th, 2012 release.