We've earlier heard Kevin Feige discussing Spider-Man and Marvel TV while attending yesterday's Avengers 2 Blu-Ray event, and now video has surfaced featuring details about Infinity War. Below you can check out the Q&A (via SlashFilm), regarding Infinity War, Feige offered the following details:
You will see the other two [Infinity Stones] some time in Phase 3 for sure. There's a Gauntlet that needs to be filled.
Regarding when Marvel started to put the Infinity Stones storyline together:
It really was sort of Iron Man 2 and building the architecture of the entirety of Phase 1 that it started to come about and the notion of the Tesseract being the not only thing that ties Phase 1 together, but that also could be a part of tieing Phase 2 together. I wouldn't say it was all perfectly planned and laid out in 2009, but that was the genesis of it. It goes back that far.
Regarding the Gauntlet seen during the Avengers 2 mid-credit scene, Feige said it's not the same one (a while back saw Feige mention there are two gauntlets). Producer Jeremy Latcham then interjected, "Which do you think is the real one?" with Feige giving him a look.
Note: The Gauntlet featured in Odin's treasure room is right-handed, while Thanos used a left-handed glove in Avengers 2 (and the Infinity War teaser). The comic book version of the Infinity Gauntlet is left-handed. We can guess Thanos may have created a fake Infinity Gauntlet to throw off Odin and the Asgardians.
Latcham also let it be known a new team of Avengers will be assembling for Marvel's Phase 4 plans.