Avengers: Age of Ultron fans can't wait to get a glimpse of the upcoming Marvel film at the 2014 San Diego Comic Con this week. While the film, scheduled for a summer 2015 release, is generating immense interest, hype and curiosity already, fans have gone a few steps ahead and started speculating on the fate, plot and design of Avengers 3!

As per latest rumours, director Joss Whedon will not return to direct the third Avengers film.

Here's an excerpt from a piece at Badass Digest. The interviewer asked James Gunn, director, about directing Avengers 3:

"He kind of sat there gobsmacked for a second. And then he said, 'It was great seeing you!'"

So no confirmation, but not a denial either. Rumours of the Guardians of the Galaxy director replacing Whedon on the director's chair for Avengers 3 have been circulating the web for quite some time now.

There are also talks that the ambitious project will act as a superhero crossover film featuring the Avengers fighting alongside Guardians against the supervillain - Thanos.

With new superheroes Quicksilver and Scarlet Witch already a part of Avengers 2 and several new superhero films (Doctor Strange, Ant-Man) slated for release as part of Marvel Studio's Phase 3 plans, reports are suggesting that Avengers 3 might just see a complete new lineup of characters. Marvel producer Kevin Feige confirmed the possibility (via IGN):

"Certainly that has been the case with the comics, right?" Feige said when asked if the Marvel Cinematic Universe was headed in that direction. "Go into the comic bin and pull up any Avengers issue from 1960-whatever and 1980-whatever, and they probably don't match. I think that's fun. That's one of the reasons why Wanda and Pietro [Quicksilver and Scarlet Witch] have shown up in the new Avengers film, because we like the notion of a shifting roster, of a growing roster," he added.