Recently, THQ shuttered its Australian studios in an attempt to cut costs and pivot away from games made for children, as well as licensed games. One of those licensed games THQ Australia in particular was working on was based on The Avengers. It apparently was to be released to complement the Avengers movie currently in production.
A YouTube video of the footage leaked on September 16th, and was blown-up for all of the Internet to see via Reddit. The video, which is just over three minutes long, has text edited over the video throughout, introducing it as pre-alpha footage of a first-person superhero romp. Plenty of moves for a variety of characters, including Iron Man and The Hulk, were shown.
The game was scheduled to hit all major consoles in time for the movie release next year.