‘The Avengers 2′ is Officially Happening
In one of the biggest "No duh!" moves in recent history, Bob Iger - Disney's CEO - announced that there will be a sequel to 'The Avengers.' After making $207 Million in its first three days domestically, after accruing over $700 million worldwide and being in a position to make well over a billion dollars by the end of its run, there was no way the film wouldn't get a sequel.
What will be interesting is who returns. Granted, most cast were signed on for multiple picture deals (we've heard up to nine films), but some of those contracts may be up, and it's possible that someone like Robert Downey Jr. could be done with his contract. And it's unknown if Joss Whedon was roped in for multiple projects - so far Marvel has had no problem bringing in new directors for sequels (see: 'Hulk,' 'Thor 2', 'Captain America 2')
That said, in the comic books The Avengers changed their line-up over the course of their adventures. This may give Marvel time to develop characters like Ant-Man or any number of other supporting players to include in this universe - or perhaps go the Hawkeye route and set them up in one film and give them a larger part in the next.
The end credits point to the direction the sequel could head (though that could just as easily be discarded), and we're at least two years away from it hitting the theaters, but it will come by hook or crook.